INTRODUCTION Texture refers to the way in which individual grains relate to grains immediately surrounding them. Texture deals with small-scale features seen in hand specimen or under the microscope, such as the degree of crystallinity, grain size, grain shape, grain orientation, grain boundary relations and crystal intergrowths. Textures are useful indicators of cooling and crystallization rates and of phase relations between minerals and magma at the time of crystallization. Igneous rocks with interlocking crystals have crystalline textures. The crystallinity and dominant grain size in crystalline igneous rocks are each described y one of a series of three terms, as shown in the figure below. TEXTURES REFERRING TO THE CRYSTALLINITY OF AN IGNEOUS ROCK The term Holocrystalline refers to a rock composed of entirely crystalline material.

Anorthosite sample which is entirely composed of Albitic plagioclase crystal

The term Holohyaline refers to a rock composed of entirely glassy material.

Obsidian sample ( volcanic glass) which is entirely composed of siliceous glassy material.

The term Hypocrystalline refers to a rock composed of both crystals and glassy material, but amount of crystals is greater than glassy material.

Andesite sample which is composed of both plagioclase (Pl) and clinopyroxene (Cpx) crystals with a fine grained groundmass. In this sample, amount of glassy material, which is essential component of the groundmass is less than the total amount of crystals.

The term Hypohyaline refers to a rock composed of both crystals and glass material but amount of glass is greater than crystals.

Rhyolitic ignimbrite sample which is composed of volcanic glass shards, pumice fragments and free crystals (Qzt-quartz; Sa-sanidine). In this sapmle amount of volcanic glass material is higher than the amount free crystals.

TEXTURES REFERRING TO THE GRANULARITY OF AN IGNEOUS ROCK Terms Which Are Used According to The Visible or Invisible Granular Properties of Igneous Rocks Phaneritic (phanerocrystalline) refers to a rock in which the grains of the essential minerals can be discerned without the aid of microscope

Polished surface of the granitic rock slab. Minerals can be distinguished clearly by naked eye.

Aphanitic refers to a rock, which is so fine grained, that individual crystals cannot be discerned without a microscope. An aphyric rock is one devoid of phenocrysts. This term is generally applied only to aphanitic or fine-grained rocks. Thus an equigranular granite, for example, devoid of phenocrysts would not be termed aphyric.

Basalt sample which contains no phenocrysts and is composed of plagioclase microphenocrysts and volcanic glass. Individual crystals can not be seen by naked eye.

Pegmatitic refers to a rock that is very coarse-grained, dominated by grains > 3 cm in length. Although many petrologists reserve the term pegmatite for siliceous (granitoid) rocks of that grain size, rocks of any composition may be pegmatitic.

Terms Which Are Used According To The Absolute Size of The Crystals The term coarse-grained implies crystal size > 5 mm. The term medium-grained implies crystal size between 1-5 mm. The term fine-grained implies crystal size < 1 mm. Terms Which Are Used According To The Relative Crystal Sizes Equigranular refers to an igneous rock texture in which the diameters of component minerals are comparable, allowing of course for the inherently tabular and prismatic, rather than equant habits of some minerals.

Biotite granite sample which is composed of nearly equigranular crystals of quartz (white), K-feldspar (grayish), plagioclase (grayish with polysynthetic twining) and biotite (reddish brown)minerals.

Porphyritic texture connotes one or more mineral species or a generation of one or more mineral species that are conspicuously greater in size than those minerals constituting the rest of the rock. There are number of larger grains called phenocrysts, surrounded by a population of grains of significantly smaller size, the groundmass.

A porphyric rock which is composed of euhedral-subhedral feldspar phenocrysts in a fine grained grounmass.

Seriate texture refers to a situation where there is a continuous range in grain size of one or more mineral species from that of phenocryst to groundmass size, and in which crystals of progressively smaller sizes are increasingly numerous. This texture is commonly shown by plagioclase in some andesite porphyries.

A volcanic rock with seriate texture. Feldspar phenocrysts especially exhibit a broad interval of grain size.

Microporphyritic texture refers to a situation where both the phenocrysts and the groundmass are aphanitic.

Basalt sample with microporphyritic texture. As it is seen in the figure, both the phenocrysts and the groundmass are fine grained (aphanitic).

Aphanitic-porphyritic and phaneritic-porphyritic term describes, respectively some situations where the phenocrysts are phaneritic but the groundmass is aphanitic and where both groundmass and phenocrysts are phaneritic.

An aphanitic-porphyritic volcanic rock which is compoded of euhedral sanidine, quartz (not visible) and some altered mafic (amphibole) minerals in an aphanitic groundmass.

Vitrophyric texture refers to a rock (vitrophyre), which is composed of phenocrysts of intratelluric crystallization in a glassy matrix.

A volcanic rock sample containing plagioclase and quartz phenocrysts in a glassy grounmass.

Microlitic texture is a porphyritic texture in which microlites (small fibrous crystals) are enclosed in a glassy groundmass.

TEXTURES REFERRING TO THE CRYSTAL SHAPES OF AN IGNEOUS ROCK Terms Which Are Used According To The Development of Crystal Surfaces Allotriomorphic refers to a texture in which all the component mineral grains are anhedral.

Dunite sample which is composed of entirely olivine (Ol) minerals and accessory enstatite (En – orthopyroxene) minerals.

Hypidiomorphic refers to a texture in which the grains of some mineral species are anhedral, those of others subhedral, and those of some may even be euhedral. This texture is typical of granitic rocks in many of which quartz and orthoclase tend to be anhedral and plagioclase and biotite are subhedral to euhedral.

Norite sample which is composed of euhedral-subhedral and anhedral plagioclase minerals (plag - gray-black colored minerals with polysynthetic twining) and subhedral-anhedral orthopyroxene (opx) and clinopyroxene (cpx) minerals.

Idiomorphic refers to a texture in which, theoretically, all the component mineral grains are euhedral (a geometrical impossibility in a holocrystalline rock). The term is commonly applied to the texture of lamprophyres, which are characteristically densely and conspicuously crowded with euhedral mafic phenocrysts.

Special Terms Referring To The Special Crystal Shapes Skeletal crystals are those which have hollows and gaps, possibly regularly developed and usually with particular crystallographic orientations. In thin section these spaces appear as embayments and holes in the crystal, filled with groundmass crystals or glass. Dendritic crystals consist of a regular array of fibres sharing a common optical orientation and having a branching pattern resembling that of a tree or the veins in a leaf or a feather. Embayed crystals are those, which have been resorbed by reaction with liquid. While this may be true of some crystals others have embayments, which probably formed during growth.

Rhyolitic volcanic rock sample that contains embayed quartz crystal (white colored). Resorbtion of quartz crystal by the melt is clearly seen in the photograph.

Parallel-growth crystals are aggregates of elongate crystals of the same mineral whose crystallographic axes are mutually parallel or almost so. Although in thin section the individual parts of the aggregate may be isolated from one another, in the third dimension they are probably connected. A parallel-growth crystal is therefore a single incomplete crystal formed by a particular style of skeletal growth.

Komatiite sample that shows parallel growth of elongate quenched olivine crystals (blue colored).

Sieve textured crystals are those which contain abundant, small, interconnected, box shaped glass inclusions, giving the crystals a spongy or porous appearance.

Sieve textured plagioclase minerals that exhibit spong core and an overgrowth surrounding this core.

Elongate, curved, branching crystals are rarely genuinely bent; rather the curvature is caused by development of branches along the length of the crystal, each branch having a slightly different crystallographic orientation to its neighbors. Pseudomorph is a secondary mineral (or group of minerals) that partly or completely replaces a pyrogenetic mineral while preserving the characteristic crystal outline of the mineral being replaced.

Amphibole pseudomorph which is partly preserved (interiors). Some parts (pale green) are chloritized.

TEXTURES REFERRING TO INTERGROWTH OF THE CRYSTALS In thin section, the junction between two crystals may appear as a straight line, a simple curve or a complex curve; in the third case the crystals interdigitate or interlock, possibly so intimately that they appear to be embedded in one another. These interpenetrative patterns are all examples of intergrowth textures. Usually the crystals concerned are anhedral but one or both may be skeletal, dendritic or radiate. Consertal texture refers to a situation where the boundary between two crystals involves interdigitations and hence appears to be notched or serrated in thin section. Graphic texture is similar to pokilitic texture in that a larger grain encloses apparently smaller grains, but this texture, which occurs in pegmatitic granitoid rocks, consists of a very large crystal of alkali feldspar enclosing smaller crystals of quartz that all have the same crystallographic orientation. In some cases it can be clearly demonstrated that the apparently separate quartz grains are all connected and are part of a large, single dendritic or snowflake quartz crystals.

Intergrowth of quartz minerals in K-feldspar crystals to form graphic texture.

Micrographic texture is compositionally akin to graphic intergrowth but the term is generally used to refer to the small interstitial patches of quartz and alkali feldspar that characterize quartz-diabeses of tholeiitic affinity. Granophyric texture delicate intergrowths, often with an overall radiating habit, of quartz and alkali feldspar in ternary minimum proportions. The texture often coarsens radially outward and passes into a micrographic texture. This transition may be apparent on a small scale within the area of one thin section and may be found also on a larger scale within intrusive bodies (typically small epizone intrusions emplaced below critical vesiculation depth), which may have granophyric margins and microgranitic interiors.

Granophyric intergrowth of quartz grains in K-feldspar.

Myrmekitic texture connotes a symplectic intergrowth of quartz and oligoclase occurring in small cauliflower-shaped embayments into microcline at oligoclase-microcline boundaries in katazonal granitic rocks and migmatites, or more rarely at oligoclase-orthoclase boundaries in some mesozonal granitic rocks. Unlike graphic and micrographic textures, which are produced by crystallization from a silicate melt, myrmekitic textures reflect subsolidus replacement effects.

Myrmekitic texture defined by wormy (rounded) intergrowths of quartz and K-feldspar in plagioclase which is adjacent to K-feldspar.

Exsolution lamellae or exsolution blebs refer to a lamellar and bleb-like intergrowths are often attributed to exsolution of the lamellae and blebs of one component from the host crystal (i.e. solid-state reaction).

Exsolution lamellae of orthopyroxene in clinopyroxene mineral (blue-purple colored).

Perthite is very common in igneous rocks and consists of quantitatively minor lamellae, shreds, patches and rims of an albite component within and around host orthoclase or microcline. Whatever the orientation in thin section, the albite component always has the higher birefringence and appears brighter under crossed nicols, a useful feature in identification, as the exsolution lamellae are generally far too small to show any diagnostic multiple twinning.

Exsolution of albite patches in microcline crystal to form perthitic texture.

Antiperthite is not commonly seen in igneous rocks and it would appear to be strictly a texture produced during metamorphism. It is also common in granulites. This texture consists of numerous tiny blebs and rods of orthoclase within the host plagioclase. Mesoperthite refers to the typical perthite of epizone granitic bodies wherein the albite component is comparable in abundance to the orthoclase component may come to form an anastomosing host around remnants of an orthoclase component (generally still relatively more abundant). Microperthite refers specifically to exsolution textures that are visible only on a microscopic scale (some perthitic intergrowths are sufficiently coarse to be conspicuous in hand specimen).

Cryptoperthite refers to even finer-grained intergrowths that are only resolvable by X-ray methods. The apparently optically homogenous sanidines of older volcanic rocks are in fact cryptoperthites (a quickly revealed by their distinctive values of 2V), their submicroscopic pattern of exsolution having been affected during the passage of time rather than during the cooling of the igneous rock. Symplectic intergrowth connotes an intimate fine-grained intergrowth of two minerals in which one mineral has a vermicular (wormlike) habit; although some symplectic intergrowths may well be due to exsolution and others may reflect post-crystallization reaction or metasomatism, some are of perplexing origin and the non-genetic connotation of the term symplectic is thus useful for descriptive purposes.

Wormlike intergrowth of very tiny quartz and K-feldspar minerals in a plagioclase mineral.

TEXTURES REFERRING TO INTERRELATIONS BETWEEN THE CRYSTALS Glomeroporphyritic texture results when phenocrysts aggregate in groups; sometimes only some of several phenocryst species may be so aggregated, suggesting that those species not involved belong to a later period of intratelluric crystallization. Some glomeroporphyritic clusters represent the incorporation of texturally more complex material, perhaps consolidated early fractionated material.

Olivine basalt sample which is composed of olivine (Ol), clinopyroxene (Cpx) phenocrysts and plagioclase microphenocrysts (not seen) in a fine grained groundmass. Note that the aggregation of clinopyroxene minerals as glomerocrysts.

Poikilitic texture is a general term describing a texture in which one or more mineral species may be partly or wholly enclosed by another mineral species. This texture indicates crystallization sequence of minerals in an igneous rock.

Biotite minerals (reddish-greenish-dark brown) poikilitically enclosed by a large K-feldspar mineral (ligh gray).

Ophitic texture is a term generally used for gabbroic rocks and refers to a situation where the dimensions of the augite crystals are substantially larger than those of the plagioclase; several even numerous plagioclase tablets may come to be included within each grain of augite.

Gabbro sample that shows extremely large crystals of enstatite (En-orthopyroxene) surrounding smaller plagioclase (Pl) crystals.

Sub-ophitic texture is a term also used for gabbroic rocks and refers to a situation where the augite grains are somewhat smaller, and not much larger than the plagioclase; they will thus only partly enclose individual plagioclase tablets.

Gabbro sample that shows clinopyroxene (various colored) minerals partly enclosing individual plagioclase minerals (with polysynthetic twinning).

Intergranular texture is characteristic for basaltic flows where the grains of augite and accessory opaque minerals small enough to fit between the unoriented array of tabular plagioclase microlites. Unlike ophitic texture, adjacent intersticies are not in optical continuity and hence are discrete small crystals. The feldspars may be in diverse, sub-radial or sub-parallel arrangement.

Dolerite sample with intergranular texture. Colored minerals are mainly anhedral clinopyroxene and olivine minerals, which are enclosed by prismatic plagioclase minerals.

Intersertal texture is characteristic of tholeiite flows where it may be present in addition to intergranular or sub-ophitic textures; although it is not present in all tholeiite flows but it is diagnostic of tholeiite where it is seen. Intersertal texture denotes the presence of small, disconnected, patches of a glassy mesostasis of acid composition, often containing numerous tiny inclusions of opaque minerals amongst the rectangular plagioclase laths that are not aligned. Glassy mesostasis may be altered in older flows generally to varieties of chlorite such as highly colored chlorophaeite.

Diabasic texture is very common in the more slowly cooled hypabyssal rocks of all basaltic compositions such as sills and some thick dykes. It is a coarse grained equivalent of the intergranular textures found in volcanic rocks. Diabasic texture is sometimes referred to as ophitic texture but two terms are not quite synonymous. Because in diabasic texture both orthopyroxene and opaque mineral as well as augite may develop a comparable poikilitic habit with respect to the plagioclase, whereas ophitic texture specifically connotes the poikilitic enclosure of plagioclase by augite alone.

Olivine basalt sample from Palisades Sill. This rocks is composed of relatively coarse grained enstatite (En-orthopyroxene), clinopyroxene (Cpx), olivine (Ol) and plagioclase (Pl) minerals.

TEXTURES REFERRING TO OVERGROWTH OF THE CRYSTALS The term overgrowth describes the partial mantling of one mineral either by material of the same composition or by material of the same mineral species but different solid-solution composition or by an unrelated mineral. This is presumably conforming to a sequence of crystallization and without conspicuous reaction. The term overgrowth carries the additional connotation of crystallographic continuity between the two participating minerals insofar as their differing crystal structures permit this. Where the overgrowth forms a more or less continuous rim around the enclosed mineral, such as, for example, the rim of plagioclase around a proportion of orthoclase phenocrysts in some textural varieties of rapakivi granite, it may be termed a mantle. Skeletal or dendritic overgrowths are found in some porphyritic rocks with a glassy or very fine-grained groundmass may show delicate fibres or plates extending from the corners or edges of the phenocrysts. The overgrowth and the phenocryst need not to be the same mineral.

Corona texture refers to a situation where a crystal o one mineral is surrounded by a rim or mantle of one or more crystals of another mineral (i.e. olivine surrounded by orthopyroxene or biotite surrounding hornblende). Such relationships are often presumed to result from incomplete reaction of the inner mineral with melt or fluid to produce the equivalent genetic terms “reaction rim” and “reaction corona” are frequently used.

Anhedral amphibole phenocryst (greenish colored interior part) surrounded by another euhedral amphibole mineral (yellowish colored), which is possibly the same type.

Reaction rim strictly results where an early-formed mineral later reacts with the still crystallizing magma. A conspicuous example is the occurrence of prominent “black rims” composed of small granules of pyroxene and opaque oxide mineral around hornblende and biotite phenocrysts in andesite and latite flows.

Basalt sample containig composite pyroxene. Subhedral orthopyroxene phenocryst with rounded margins (inner part), is surrounded by clinopyroxene rim (red-yellow colored) due to reaction with the melt.

Kelyphitic rims refer to a microcrystalline overgrowth of fibrous pyroxene or hornblende or olivine or garnet. This texture is found in altered coarse-grained igneous rocks, around the boundaries of crystals, reflecting partial degradation of the pyrogenetic mineralogy under low-grade metamorphic conditions. Rapakivi texture is a special term used to describe an overgrowth by sodic plagioclase on large, usually round, K-feldspar crystals. Epitaxial refers to a situation where one mineral grows around another in such a way that their crystallographic structures are continuous from one to the other.

Terms Which Are Used For The Crystal Zoning One or more concentric bands in a single crystal are picked out by lines of inclusions or by gradual or abrupt changes in solid-solution composition of the crystal.

Aegirine-augite crystal showing crystal zoning. Note that the concentric euhedral zones in the crystal.

Normal zoning connotes the gradual transition during the growth of a crystal (from core to rim) to a relatively low-temperature composition in a crystalline solution series. It is the anticipated result of fractional crystallization where equilibrium has failed to keep up with falling liquidus composition. Reverse zoning in contrast, connotes the transition generally abrupt to a higher temperature outer zone in a crystal. Some hiatal event such as an accession of fresh magma to a magma chamber undergoing fractional crystallization or sudden loss of volatiles from a sub-volcanic magma chamber is responsible for reverse zoning. Multiple zoning is used for crystals having repeated discontinuous zones. If the zones show a rhythmic repetition of width, the pattern is known as oscillatory zoning. The overall compositional trend of the multiple zoning may be normal or reverse or even (in which there is no general trend from core to rim). Individual zones may be of uniform or variable composition, such that the zoning pattern on a composition-distance graph is square wave, step-like, saw-tooth, curved saw-tooth, or some combination of these. Oscillatory zoning generally accompanies reverse zoning and refers to a succession of normally zoned shells in a crystal each separated by a sharp reverse zone. Oscillatory zoning is often evident in the plagioclase phenocrysts of andesite, originating intratellurically in high level magma chambers where a complex crystallization history is inferred. Convolute zoning is a variety of multiple zoning in which some of the zones are erratic and have non-uniform thickness. Sector (or hourglass) zoning is a common feature of pyroxenes in alkali-rich basic and ultrabasic rocks. It has also been seen in plagioclases in a few quickly cooled basalts. In this type of zoning, a crystal takes the form of four triangular segments (sectors) with a common apex. Opposite sectors are chemically identical whereas adjacent ones differ in composition (though possibly only slightly) and hence in optical properties. Each sector may be homogenous or show continuous or discontinuous or oscillatory, normal or reverse or ever zoning. In three dimensions the sectors are pyramid shaped. If the sector boundaries are curved, the pattern can resemble that of an hourglass.

TEXTURES REFERRING TO RADIAL ARRANGEMENT OF THE CRYSTALS Radiate textures are those in which elongate crystals diverge from a common nucleus. They are most frequently found in fine-grained rocks, but not exclusively. A remarkably large number of terms exist to describe the various patterns, including, fan, plume, spray, bow-tie, spherical, sheaf-like, radiate, radial, axiolitic, spherulitic and variolitic. All except the last three are of self evident meaning. Spherulitic texture is composed of an aggregate of fibrous crystals of one or more minerals radiating from a nucleus, with glass or crystals in between. The acicular crystals may be either single, simple fibres or each may have branches along its length; any branches may or may not share the same optical orientations as their parents. The most common occurrence of spherulitic texture is a radiate aggregate of acicular alkali-feldspars with glass between them, though quartz or other minerals may be present, resulting in an intergrowth texture. Axiolites differ from spherulites in that radiating fibres extend from either end of a linear nucleus (i.e. from a small acicular crystal) rather than a point. They could be regarded as a variety of overgrowth texture, as indeed could those spherulites which grow about visible crystals rather than a submicroscopic nuclei.

Spherulites are radiating masses of fibrous crystals in a glassy matrix. These spherulites are probably composed of alkali feldspars and some polymorph of SiO2, and in this cross-polarized shot, appear as round objects with dark crosses. Note the large phenocryst which forms the nucleus of one of the spherulites at center-left.

Variolitic texture is composed of a fan-like arrangement of divergent, often branching, fibres; usually the fibres are plagioclase and glass or granules of pyroxene, olivine or iron ore occupy the space between. This texture differs from spherulitic texture in that no discrete spherical bodies are identifiable; in fact, each fan as seen in thin section is a slice through a conical bundle of acicular crystals.

TEXTURES REFERRING TO CAVITY FILLINGS OF THE CRYSTALS These are a collection of textures, which feature either holes in the rock, or likely former holes which are now partly or completely filled with crystals. Vesicular texture refers to a round, ovoid or elongates irregular holes (vesicles) formed by expansion of gas in magma.

Scoria sample containing ovoidal vesicles (dark regions).

Amygdaloidal texture refers to a former vesicles which are occupied, or partially occupied by late stage magmatic and/or post magmatic minerals, such as, carbonate, zeolites, quartz, chalcedony, analcite, chlorite and/or rarely, glass or fine groundmass. The filled holes are known as “amygdales” or “amygdules”.

The oval feature in this photomicrograph is an amygdule: a formerly open vesicle which has been filled with a secondary mineral(s) precipitated from low-T ground waters which have penetrated into the rock.

Ocellar texture refers to a certain spherical or ellipsoidal leucocratic patches enclosed in more mafic hosts are known as ocelli (singular ocellus). Unlike amygdales, the minerals filling an ocellus can normally all be

found in the host rock; they may include any of; nepheline, analcite, zeolite, calcite, leucite, K-feldspar, Na-feldspar, quartz, chlorite, biotite, hornblende and pyroxene, or even glass, and the minerals are commonly distributed in a zonal arrangement. Often, platy and acicular crystals in the host bordering an ocellus are tangentially arranged but sometimes project into the ocellus. Ocelli are normally less than 5 mm in diameter but may reach 2 cm. Their origin has been ascribed on the one hand to separation of droplets of immiscible liquid from magma, and on the other hand to seepage of residual liquid or fluid into vesicles. Miarolitic texture refers to irregularly shaped cavities (druses) in plutonic and hypabyssal rocks into which euhedral crystals of the rock project. OTHER TERMS REFERRING TO THE TEXTURES OF IGNEOUS ROCKS Devitrification refers in general to the transformation with time of originally glassy groundmass or mesostasis material to a fine-grained cryptocrystalline or microcrystalline product. The patterns of devitrification textures can be quite varied and superimposed, for example, on primary features such as perlitic fractures or the outlines of shards in an ignimbrite, where varying degrees of primary devitrification may have occurred varying with height in the cooling unit. Devitrification processes in ignimbrites occur in two stages: (1) a “primary devitrification” while the ignimbritic cooling unit is cooling, commonly results in a complete fine-grained devitrification of the groundmass of the entire upper portion of the ignimbrite cooling unit, often associated with vague spherulitic devitrification textures within pumice fragments; and (2) a “secondary devitrification” with the prolonged passage of time will come to affect all glassy material not devitrified by the primary devitrification. Relict textures refer to such features as preservation of shard outlines and perlitic cracks in some devitrified ignimbrites and glassy rhyolite flows respectively, or the presence of small kernels of fresh olivine within a crystal that may be nearly completely pseudomorphed by a mesh of serpentine. Felsitic texture results from slow devitrification over geologically long periods of time of rhyolitic material originally cooled to a glass; in felsitic texture aggregates of cryptocrystalline or very fine-grained microcrystalline material extinguish together in small patches throughout the rock. Eutaxitic texture results from varying degrees of flattening and welding of glassy shards of groundmass in ignimbrites, which are the characteristic volcanic product of rhyolite eruptions.

Cumulus texture is best recognized by distinctive layering of cumulate rocks in the outcrop. Where there is only one cumulus phase, the cumulate nature of the rocks is generally evident from the (varied) nature of intercumulus growth such as oikocrysts and adcumulus growth. Gabbroic texture results where all the grains tend to be anhedral with intergrown irregular boundaries but may retain an overall subhedral outline (i.e. each cumulus grain has acted as a convenient nucleation center for intercumulus growth).

Gabbro sample which is composed of anhedral clinopyroxene (colored minerals) and subhedral-anhedral plagioclase minerals (grayish-white colored).

Granitic texture connotes a granitic rock, which is both equigranular and hypidiomorphic – the common condition.

Biotite granite sample which is nearly equigranular and composed of Biotite (reddish), quartz (wihe), plagioclase and K-feldspar (grayish) minerals those are subhedral to anhedral in habit.

Monzonitic texture is a specific type of poikilitic texture in which orthoclase (often perthitic) poikilitically encloses crystals of plagioclase (that often display limpid albite rims in this situation) and mafic minerals.

Aplitic texture refers to a fine-grained rock, often occurring as narrow aplite veins, generally of ideal granite composition, in which all the felsic minerals are equigranular and anhedral.

Aplite samples with quartz phenocrysts in the fine grained holocrystalline part Of the rock. Fine grained part is composed mainly of quartz and K-feldspar.

Lamprophyric texture refers to the voluminously porphyritic, apparently panidiomorphic texture that is common in lamprophyric rocks.