Geology wordbook of hand-picked Necessary Terms

Absorption Spectrum : 

Colours of sunshine least absorbed combining to provide the colour of the stone. The stone, once viewed by prism spectroscope, can show as dark bands in characteristic positions the colours most powerfully absorbed.

Acicular : 

Needlelike; refers to the expansion of a mineral in long and slender crystals.

Adamantine : terribly high luster.

Aggregate : Intergrowth of many crystals, these could also be spheric, fibrous, reniform, or diverging fibrous.

Adularescence : The radiancy of color seen in feldspar and different feldspars of the adularia selection.

Allochromatic Minerals : Minerals that square measure colorless once pure, the colour coming back from coloring agents, most of that square measure, cobalt, copper, chromium, titanium, vanadium, manganese, and iron. samples of this square measure mineral,corundum, quartz, and spinel.

Alluvium : Continental sediments thanks to transport and deposition of gravel, sand, and clay by running water, rivers, and streams. (See alluvial)

Alpha rays : He atoms with double electric charge.

Alpine cavities (vugs) : Hollows in salt rock, they'll be part stuffed with mineral formations.

Alteration pseudomorph : One mineral has been replaced by another that's unrelated whereas conserving the initial crystal kind.

Amorphous : Has no characteristic external kind or form. The arrangement of the atoms and molecules square measure irregular

Amphiboles : a gaggle of closely connected, dark coloured rock forming salt minerals, as in, actinolite, hornblende.

Anisotropic : once applied to crystals it's the show of unequal physical properties in several directions. associate example would be a mineral that features a completely different hardness once tested in several directions.

Amygdaloidal : (amygdule) gas stuffed igneous rock.

Amygdule : A rounded mass of mineral shaped in an exceedingly gas cavity.

Angstrom Unit : Unit and length of measure of wavelengths of visible radiation and most xrays. (1 A.= .0000001 millimeter)

Anisotropic : Crystals during which the optical properties vary with direction. All crystals except those within the cubelike system square measure during this class, and exhibit refraction.

Aphanitic rock :  That rock during which the crystals square measure too tiny to be seen by the unaided eye.

Arid :  dry or desert like.

Arsenates : Minerals during which AsO4 radical is a crucial constituent.

Asterism : Stones containing appropriately oriented  rod like inclusions or channels, that square measure cut as gemstone within the correct direction show this star result. Star result.

Atom : the tiniest a part of a matter that remains unchanged throughout all chemical reactions. mass : Weight of associate atom compared with associate atom of element (16.00).

Batholith : a large body of igneous rock that has been intruded deep into the layer and latter exposed by erosion.

Bean (pisolitic) ore : spheric aggregates of iron ore that occur in karst cavities as weathering formations.

Bita rays : negatron rays

Bezel :  A rim of metal encompassing a gem securing it.

Biaxial : 2 optic axes or refraction. sometimes crystals within the parallelogram, monoclinic, and triclinic  system.

Bipyramid (dipyramid) : Crystals that kind symmetrically a few plane dividing it into 2 pyramids.

Birefringence : Same as refraction. Splits rays of sunshine passing through a clear object as glass or crystal.

Botryoidal :  Resembling a bunch of grapes in rounded lots of a mineral.

Boule : {the form|the form} and shape of an artificial stone once created by the inverted blowpipe of a Verneuil chamber, somewhat carrot formed.

Breccia : associate combination of angular fragments of stone or mineral cemented along as in spar and quartz.

Brilliant : The cut of a gem that's spherical and has thirty two aspects and the table on top of the girdle, (crown), and twenty four aspects and any culet below the girdle, (pavilion).

Cabochon : The cut of a gem that features a bell-shaped surface. A cab.

Cameo :  A lapidarian shell, generally cut from chalcedony or different mineral containing bands of various colours, to chop in relief, the other of intaglio.

Carat : Unit of weight wont to weigh gemstones, up to two hundred milligrams, or .200 grams. 1 gr. = 5 ct. one hundred points = one ct. system of weights and measures.

Cataclastic rock :  A rock made by the crushing and grinding of preceding rocks, that square measure still visible as crushed fragments.

Chatoyancy : opaque gem result made by some gemstones once cut properly in gemstone. See asterism.

Chelsea Filter : A dichromatic color filter transmission lightweight of solely 2 wavelengths, one red the opposite chartreuse. wont to discriminate between emerald and synth. mineral and inexperienced glass coloured with metal.

Chemical Element : Matter composed of atoms of only 1 chemical sort that can't be rotten into less complicated substances by chemical ways.

Clastic rock : rock created from fragments of preceding rocks and transported into the place of deposition.

Cleavage : The tendency of stones to separate on one or additional definite directions, perpetually parallel to a attainable crystal face.

Conchoidal..(fracture), A breakage that leaves a conchoidal shell formed surface.

Conglomerate ( as in geology) .. Conglomerates, furthermore as substance breccias, square measure coarse-grained substance ROCKS shaped by the consolidation and hardening of, severally, rounded and angular gravel deposited in oceans. over thirty % of the massive particles of those rocks exceed a pair of millimetre (0.08 in) in diameter. The particles could also be pebbles, cobbles, or boulders, or mixtures of those sizes. each conglomerates and substance breccias could also be named and classified by the proportion of gravel - sized particles; the kind of matrix,and the varieties of gravel-sized particles. The proportion of gravel could be a operate of the best current speed at the time of deposition and also the availableness of particles of such coarse size. A sample that's over eighty % pebbles, cobbles, or boulders is termed a conglomerate correct, whereas one that's thirty to eighty % is associate arenaceous  (sandy) conglomerate or associate argillaceous  (shaley) conglomerate. The matrix between the layers of coarse particles might also be chalky (that is, containing metallic element carbonate) or sideritic (containing metal carbonate). On the idea of the variability of pebbles, cobbles, and boulders in conglomerates, they will be classified as oligomictic, consisting of one quite rock (such mutually of assorted forms of silica and stone or different rock), or polymictic, containing several forms of rock.

Concretion : unshapely or rounded mineral concentrations in substance rocks that square measure utterly enclosed by rock.

Contact geologic process : The amendment of rock thanks to the result of high temperatures throughout contact with a volcanic rock flow, stone sloping, or igneous intrusion.

Critical Angle : The angle at that a ray of sunshine passes from one medium to a different, as a gem and air. Cryptocrystalline :  : The structure of a substance as quartz, that accommodates terribly tiny crystals however show no external sign of crystal structure.

Crystal : A homogenised body within the sort of a geometrical solid secure by solid faces, the character of that is expression of the orderly and periodic arrangement of its constituent atoms.

Crystal Axes : "Lines" passing through a crystal in necessary biradial directions, across at the middle of the crystal.

Crystal Systems : The six main teams into that crystals is classified: triclinic , monoclinic, orthorhombic, cubic, polygonal shape and hexangular.

Decrepitation :  The explosive shattering of mineral grains on heating.

Dendrites :  Skeletal crystals that develop from concentrated solutions, usually in tiny cracks, usually resembling plant or trees.

Density : The quantitative relation of the load of a substance to its volume expressed in g/cm three, and numerically up to the precise gravity.

Detrital : prevalence of minerals in gravels that came from a mineral deposit. (placer)

Diaphaneity : Showing lightweight through its substance; transparent; semitransparent.

Dichroism : Possessing the property of showing 2 {different|totally completely different|completely different} colours once viewed from different angles.

Dike : within the forming of rocks, once intrusive substance rocks in an exceedingly vertical or nearly vertical position.

Dispersion : The separation of white lightweight into its constituent colours by its refraction or optical phenomenon.

Double Refraction : Ability of bound crystals to separate incident lightweight into 2 rays with completely different refractive indices.

Doublets : a typical technique of build up sufficient  thickness to allow a gem to be utilized in a setting. A non gem mineral is cemented to the highest or bottom of the gem material. (See Opals.)

Dripstone : stalagmites or stalactites

Druse : A crystal coated surface of rock.

Doctile : ready to be drawn into a wire.

Endogenous : Generated deep within the earth by geological phenomenon or earthquakes.

Enhydro : A quartz or calcedony nodule having the middle cavity stuffed with water.

Epithermal vein : shaped at shallow depths from ascending hot solutions.

Epizone : In regional geologic process, the depth level nearest the surface to approx. 3.75 to 4.25 miles.

Extinction : Diminution within the intensity of radiation thanks to absorption by or scattering within the medium; additionally the stopping of incident X-rays by the outer layers of atoms in an exceedingly crystal.

Extraordinary Ray : Crystals and minerals happiness to the hexangular polygonal shape systems during which the ray or index of refraction varies in step with its direction through the crystal.

Extrusive rock : rock that solidifies on the surface of the planet.

Facet : simulated flat a part of a mineral, a placoid surface.

Ferromagnetism : magnetic even within the absence of associate external field.

Fire : Same as dispersion

Fluorescence : Temporary emission of radiations of various wavelength (color) by a substance stricken by light-weight waves typically long or radio radiation actinic ray.

Fluvial : Deposits from rivers.

Foliated : created of skinny leaves, like mica.

Formulas : For weight estimation supported measurements in millimeters to 1/10. assumptive well cut stones with very little or no bulge issue. Some formulas for varied gem cuts.

Fracture : a prospect with associate uneven or irregular surface.

Fraunhofer Lines : A series of teams of dark lines within the spectrum of associate object, visible employing a prism spectroscope.

Friable : simply fragmented or powdered.

Fumaroles : Spots in or close to active volcanos wherever gases square measure expelled.

Gabgue : The minerals of no price in veins with ore minerals.

Gamma rays : radio radiation magnetism waves.

Gangue : Minerals of no price associated in veins with ore minerals.

Geniculated :  Knee like intergrowths of crystals.

Geode : A stone having a cavity lined with crystals; the cavity in such a stone.

Girdle : The wide a part of a cut gem

Gliding plane :  acrystal direction on that the atoms will slip an outlined distance while not destroying the coherence of the crystal.

Grain : (Troy system)..480 grains to the oz.

Habit : Characteristic crystal kind.

Hacklt : A fracture characteristic of metals in rock, like gold and copper. (hackly)

Hardness : The resistance by a substance to actions that tend to change its surface by scratching, abrasion, penetration.

Hemimorphic : 0.5 shaped crystals within which the faces that grow on one finish square measure completely different in angle and position from the faces to be found on the opposite finish.

Hydrothermal : quandary or answer typically superheated

Idiochromatic : Minerals : within which the colour is because of a vital constituent.

Igneous rock : Rock shaped by the activity of rock.

Inclusions : Substances among a mineral, example, alternative minerals, gas bubbles, liquids, or alternative foreign objects.

Imitation Stones : Substances accustomed appear as if a real. ie: glass, plastic, etc.

Inclusions : Solid, gaseous, or liquid material of varied sorts incorporated in a very crystal throughout its formation and growth.

Intaglio : Incised carving; a sunken style, ie: cameo

Intarsia : Mosaic inlay work exploitation coloured stones. (and wood)

Ion : Electrically charged atom, radical or molecule.

Isomorphous  : Minerals within which 2 or a lot of components will replace one another to any extent while not notably dynamical the looks of the crystal.

Isotropic : Materials within which the optical character is that the same altogether directions.

Labradorescence : uneven or diffuse opalescence because of the interference of sunshine by reflection from parallel inclusions. Example Labradorite.

Light : energy which supplies the feeling of sight. speed is 186,285 miles per second.

Litmus paper : coloured paper accustomed show whether or not an answer is acid or alcalescent.

Lopolith A large, lenticular, sunken mass of stone whose surfaces square measure concordant with the enclosure rocks.

Luster : A reflective property of mineral surfaces.

Magma : liquified silicon oxide containing volatile substances in answer, gift below the surface in bound areas of the crust.

Malleable : is two-dimensional by pounding, as in metals.

Mammillary :  rounded mineral surface

Massive : Minerals not finite by crystal faces.

Metamorphism : (geological)..Changes in rocks led to by heat and pressure acting within the rocks slightly below the surface.

Meteorite : Solid object that comes from space and falls to earth.

Miaroles : tiny cavities in granitic rocks created by volatile parts.

Miller indices : cluster of 3 digits accustomed designate crystal faces.

Mohs Scale : The relative scale of the hardness of minerals, from one to ten, the order of hardness with no significance to quantitative relationship.

Molecule : 2 or a lot of atoms in shut relationship, the tiniest amount of a part or compound that is capable of freelance existence.

Monochromatic light-weight : light-weight of 1 wavelength solely.

Nicol Prism : Prism for manufacturing polarized light-weight, having split the sunshine into 2 rays.

Nodule : A lump or node.

Opaque : Not clear or clear. (you cannot see through it)

Optic Axis : The direction of single refraction in a very double refractive mineral.

Optic sign : If the lower index of the refractive reading doesn't vary once the gem is turned, it's uniaxial and + optic sign, if the upper index is steady and also the lower index varies the optical sign is -.

Ore :  A mineral occurring in enough amounts to allow its recovery at a profit.

Organic : compounds of carbon, ie: coal, jet

Orient : Characteristic radiancy and opalescence, as displayed in a very smart pearl. v Orientation :  Applied to crystals, this suggests visualizing the disposition of the principal directions among the crystal.

Orogenesis : a fancy phenomena that results in the formation of mountain ranges.

Outcrop : wherever the bed rock is exposed.

Paleontology :  a division of earth science that considerations itself with prehistoric life.

Paragenesis : The sequence in time within which a mineral crystallizes with relevance the opposite minerals.

Paramorph : A with chemicals identical crystal compared with the first, however the atoms are rearranged in order that they now not adjust to the first define.

Parting : A sleek fracture that appears sort of a cleavage plane however takes place solely on bound planes within the crystal, not between any set of atoms, like true cleavage.

Paste : glass imitation stone.

Pegmatites : .A very coarse platonic rock, usually granitic in composition. typically forming dikes that cut granite or the gneisses and schists that border granite plenty. they're coarse as a result of the liquid residue at the time of their crystallization contained a high proportion of water and alternative volatile components that failed to move into the makeup of the common minerals of granite, and were focused within the residue.

Petrography : The branch of earth science that deals with the outline and classification of rocks.

Phaneritic rock : associate stone within which all of the essential minerals is seen by the unaided eye.

Phenocryst : Crystal that's set in a very finer grained ground mass.

Phosphorescence : Luminescence emanating from substances that are irradiated with actinic ray or X-rays, however uninterrupted when the supply of stimulation has stopped.

Piezoelectric : A substance that becomes electrically charged by pressure.

Pipe : In earth science, the cannular ascending structures in igneous rock.

Placer : Concentrations of serious or resistant minerals that are transported to rivers or alternative water areas.

Plastics : rosin, hard, typically formed.

Pleochroism : pleochroism and similar effects shown by some biaxal minerals within which 3 distinct colours or shades is seen by employing a dichroscope. (two at a time)

Plutonic rock : rock that has solid deep underground.

Pneumatolysis : The action of gases of a rock on the encompassing rocks and on the activity liquified mass itself. purpose : (diamonds).. 1/100 of a carat, .01 ct.

Polarized light-weight : light-weight that vibrates in one direction or plane.

Polaroid : category or plastic that passes light-weight on one plane.

Potch : native material in or around a gem, a dead spot or space. ie: ironstone close mineral.

Radioactive : Emitting alpha, beta, or gamma rays.

Reconstructed Stones : previous methodology of fusing Stones made of chips. Used currently to explain amber remelted and consolidated from otherwise unusable items.

Reflection : The throwing off or back, light-weight from the surface.

Refraction : The bending of sunshine passing through one medium to a different. The dynamic  of direction.

Refractive Index : The measuring of the quantity of amendment in direction of sunshine passing through one medium to a different. The magnitude relation of the rate of the sunshine in air to the rate of sunshine within the medium being measured.

Refractometer : Instrument accustomed verify the index of refraction of assorted substances.

Rock : Stoney matter. Any mass of mineral matter forming a necessary a part of the crust.

Sclerometer : Device for the quantitative measure of hardness.

Sedimentary Rocks : fashioned originally of sediment, as well as sedimentary rock and arenaceous rock, composed of fragments of alternative rocks deposited once transportation from their sources, and as well as those fashioned by precipitation, as gypsum, or by chalky secretions of animals as in sure limestones.

Selvage : the realm bordering a vein.

Sheen : The brightness of sunshine mirrored from the surface of a stone. ie: felspar

Silk : Fine rod like crystals embedded in a very crystal

 

Skarn : Contact rock of igneous salt lots with rock.

Specific Gravity : the load of a substance compared to the load of associate equal volume of pure water at four degrees C.

Spectroscope : Instrument that resolves light-weight into its part wavelengths by refraction through prisms or grating.

Spectrum : The band of sunshine showing the succession of rainbow colours admire the various wavelengths. The color spectrum is that the tiny portion within the Brobdingnagian spectrum of magnetism waves, that extend from terribly long waves, (now utilized by submarines for underwater communication) to terribly short waves (gamma) emitted by hot parts.

Stalactites : dripstone, stalagmite..the formation of a conical structure that grows from the deposits of carbonate of lime build up.

Star : The result of correct cutting of a stone as a gem once the stone contains long rod like crystals or fibers in parallel or cavities wherever these have formally been. The reflection, (using one light-weight source), from the surface produces lines in even numbers, ie: 2,4,6,8,12, with a typical center.

Step cut (trap cut) : Cut with edges square measure parallel to those the oblong table.

Synthetic stones : non-natural stones that have approx. identical composition and or crystal structure of the natural crystal that they represent. (See artificial diamonds.)

Transparency : The degree to that light-weight passes through a substance.

Twin Crystals : 2 or additional crystals that have full-grown along in a very symmetrical fashion.

Ultraviolet Light : Wavelengths {of light-weight|of sunshine} shorter than visible violet light.

 

Ultrabasic rock : Any intrusive rock with terribly low oxide content.

Uniaxial : Minerals having single refraction, one principal axis.

Vacuolar texture : texture typical of igneous rocks wealthy in cavities.

Vectorial properties : properties of a mineral that vary with direction.

Vein : A additional or less upright sheet deposit of minerals, cutting alternative rocks and fashioned from solutions instead of from a melted  rock as in a very dike.

Vicarious parts : those who take every other's place in trace amounts in a very mineral,s crystal structure. Vitreous.. Glasslike in look or texture.

Vug : associate open cavity in rocks, typically lined with crystals.

Xenolith : rock closed in in rock.

X- rays : magnetism radiations of a shorter wavelength than actinic ray. typically but one angstrom unit.