This page is intended to be a list of rock textural and morphological terms.

A

* Adcumulate * Agglomeritic * Adamantine a type of lustre * Amygdaloidal * Anhedral * Antitaxial veins *

Aphanitic Aphanites (adj. ''aphanitic''; ) are igneous rocks that are so fine-grained that their component mineral crystals are not visible to the naked eye (in contrast to phanerites, in which the crystals are visible to the unaided eye). This ge ...

* Aplitic; aplite * Augen textured gneiss * Axiolitic texture

B

* Botryoidal *

Breccia Breccia () is a rock composed of large angular broken fragments of minerals or rocks cemented together by a fine-grained matrix. The word has its origins in the Italian language, in which it means "rubble". A breccia may have a variety of ...

ted * Bedding fissile; bedding fissility *

Boudinage Boudinaged quartz vein in shear foliation, Starlight Pit, Fortnum Gold Mine, Western Australia. Boudinage is a geological term for structures formed by extension, where a rigid tabular body such as hornfels, is stretched and deformed amids ...

; boudins

C

* Cataclastic * Chilled margin *

Clastic Clastic rocks are composed of fragments, or clasts, of pre-existing minerals and rock. A clast is a fragment of geological detritus,Essentials of Geology, 3rd Ed, Stephen Marshak, p. G-3 chunks, and smaller grains of rock broken off other rocks ...

; see also

breccia Breccia () is a rock composed of large angular broken fragments of minerals or rocks cemented together by a fine-grained matrix. The word has its origins in the Italian language, in which it means "rubble". A breccia may have a variety of ...

* Cleaved * Crenulated * Cross-bedding * Cross-stratification; also trough-cross stratification. *

Cumulate Cumulate rocks are igneous rocks formed by the accumulation of crystals from a magma either by settling or floating. Cumulate rocks are named according to their texture; cumulate texture is diagnostic of the conditions of formation of this group o ...

; see also layered intrusion

D

* Decussate * Devitirification; devitrified * Dendritic texture; dendrites * Diatextite; see also schlieren and migmatite

E

* Embayed minerals; see igneous texture * Equigranular *

Euhedral Euhedral crystals (also known as idiomorphic or automorphic crystals) are those that are well-formed, with sharp, easily recognised faces. The opposite is anhedral (also known as '' xenomorphic'' or ''allotriomorphic''): a rock with an anhedr ...

* Eutaxitic * Epiclastic

F

* Fiamme * Foliation * Fissile; see also Bedding fissility. *

Fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

iferous

G

* Glomeroporphyritic *

Gneiss Gneiss ( ) is a common and widely distributed type of metamorphic rock. It is formed by high-temperature and high-pressure metamorphic processes acting on formations composed of igneous or sedimentary rocks. Gneiss forms at higher temperatures a ...

ose; gneissic * Granoblastic * Granophyric * Granulitic * Graphic

H

* Holocrystalline * Hyaline texture * Hyalopilitic

I

* Imbricate

J

* Jointed

K

* Kelyphitic

L

* Lepidoblastic * Leucocratic * Lineation, lineated * L-tectonite

M

* Melanocratic * Mesocratic * Mesocumulate * Mylonitic

N

* Nematoblastic

O

* Ocelli * Oolitic; see also

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms w ...

* Ophitic texture *

Orbicular Orbicular is an adjective meaning "circular" Orbicular may also refer to: * Orbicular leaf, a plant leaf shape * Orbicularis oculi muscle, a muscle around the eye * Orbicularis oris muscle, a muscle around the mouth * Orbicular batfish, a spec ...

texture * Orthocumulate

P

* Panidiomorphic * Pegmatitic * Peloidal * Perthitic * Phaneritic * Phyllitic * Pisolitic * Poikilitic *

Poikiloblast A poikiloblast is a porphyroblast mineral with small inclusions of the previous rock in it. From the texture (if any) shown in the inclusion, the deformation history of the rock can be interpreted, as the inclusions are always older than the po ...

ic *

Porphyroclast 350px, A mylonite showing a number of (rotated) porphyroclasts: a clear red garnet left in the picture while smaller white feldspar porphyroclasts can be found all over. ''Location'': the tectonics, tectonic contact between the wiktionary:autochth ...

ic * Porphyroblastic *

Porphyritic texture Porphyritic is an adjective used in geology to describe igneous rocks with a distinct difference in the size of mineral crystals, with the larger crystals known as phenocrysts. Both extrusive and intrusive rocks can be porphyritic, meaning all ...

; see also porphyry *

Ptygmatic In structural geology, a fold is a stack of originally planar surfaces, such as sedimentary strata, that are bent or curved during permanent deformation. Folds in rocks vary in size from microscopic crinkles to mountain-sized folds. They occur ...

(folding); see migmatite

Q

* Quench textures; see

obsidian Obsidian () is a naturally occurring volcanic glass formed when lava extruded from a volcano cools rapidly with minimal crystal growth. It is an igneous rock. Obsidian is produced from felsic lava, rich in the lighter elements such as silicon ...

tachylyte Tachylite ( ; also spelled tachylyte) is a form of basaltic volcanic glass. This glass is formed naturally by the rapid cooling of molten basalt. It is a type of mafic igneous rock that is decomposable by acids and readily fusible. The color ...

aphanitic Aphanites (adj. ''aphanitic''; ) are igneous rocks that are so fine-grained that their component mineral crystals are not visible to the naked eye (in contrast to phanerites, in which the crystals are visible to the unaided eye). This ge ...

R

* Rapakivi texture

S

Sand Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class ...

y *

Schistose Schist ( ) is a medium-grained metamorphic rock showing pronounced schistosity. This means that the rock is composed of mineral grains easily seen with a low-power hand lens, oriented in such a way that the rock is easily split into thin flakes ...

; schistosity *

Seriate texture Seriate ( Bergamasque: Help:IPA/Italian_dialects">sɛˈɾjat.html" ;"title="Help:IPA/Italian_dialects.html" ;"title="nowiki/> sɛˈɾjat">Help:IPA/Italian_dialects.html"_;"title="nowiki/>Help:IPA/Italian_dialects">sɛˈɾjatref_name=":0"_/>_) ...

* Shear; sheared; shear fabric *

Slaty Slate gray is a gray color with a slight azure tinge that is a representation of the average color of the material slate. As a tertiary color, slate is an equal mix of purple and green pigments. Slaty, referring to this color, is often used to ...

; slaty cleavage * Specular * Spherulite * Spinifex texture; see also

komatiite Komatiite () is a type of ultramafic mantle-derived volcanic rock defined as having crystallised from a lava of at least 18 wt% MgO. Komatiites have low silicon, potassium and aluminium, and high to extremely high magnesium content. Komatiite w ...

* S-tectonite * Stratabound *

Stratum In geology and related fields, a stratum ( : strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as e ...

* Stromatolitic * Stylolitic *

Subhedral Euhedral crystals (also known as idiomorphic or automorphic crystals) are those that are well-formed, with sharp, easily recognised faces. The opposite is anhedral (also known as '' xenomorphic'' or ''allotriomorphic''): a rock with an anhedra ...

Symplectite A symplectite (or symplektite) is a material texture: a micrometre-scale or submicrometre-scale intergrowth of two or more crystals. Symplectites form from the breakdown of unstable phases, and may be composed of minerals, ceramics, or metals. Fund ...

T

Tuff Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption. Following ejection and deposition, the ash is lithified into a solid rock. Rock that contains greater than 75% ash is considered tuff, while rock ...

aceous * Trachytic texture

U

V

* Vesicular texture * Variolitic *

Vitreous Vitreous may refer to: Materials * Glass, an amorphous solid material ** Vitreous enamel, a material made by fusing powdered glass to a substrate by firing * Vitreous lustre, a glassy luster or sheen on a mineral surface Biology * Vitreous bod ...

* Vuggy

A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

T

U

V

W - Z

See also