Minerals Quiz Flashcards
Crystallography
Scientific study of the structure and symmetry of crystals
Crystal Faces
The planar, flat surfaces of a mineral grain that stopped growing when it was still in contact with gas or liquid.
Chemical properties
Some minerals react with dilute hydrochloric acid. Other minerals taste salty as a result of chemical reactions that take place on the surface of our tongues.
Physical properties
Determined by the mineral composition structure colour and the Lester of its surface.
Colour
Different colours are related to the impurities.
Streak
The colour of a fine green powder of a mineral is called a streak.
Luster
Appearance of a mineral surface in reflected light
Metallic minerals
Often subject to oxidation, tarnish, or other forms of chemical weathering that might alter their appearance
Thin sections
Carefully ground slices of minerals and rocks mounted on glass slides
Submetallic lustre
Elester that seems intermediate between metallic and nonmetallic. Might be affected by tarnish or oxidation like rust on steel
Vitreous
Resembles the lustre or sheen of glass
Resinous
Resembles a resin like Amber or dried Tree sap
Silky
A silk like reflection of light from thin parallel mineral fiber’s
Pearly
Resembles lustre of a pearl
Earthy
Lacking reflection like dry soil (dull)
Waxy
Resembles wax
Satin
Resemble Sat and cloth
Greasy
Looks like it’s covered in a thin film of oil or grease
Opaque minerals
Do not allow light to pass through them
Euhedral
Well developed Crystal faces. Only develop if Crystal is unrestricted as it grows in a gas or liquid
Subhedral
Mineral grains are partly bound by well formed crystals
Anhedral
Mineral grains grew into the space between existing solid mineral greens and have no apparent crystal faces on their grain boundaries
Cleavage
The tendency of some minerals to break Along flat, parallel surfaces
No cleavage
No broken parallel surfaces
One cleavage
Basal (book) Cleavage. Split apart along flat sheets
Two cleavage is intersect at or near 90°
Prismatic cleavage. Elongated forms that fracture a long short rectangular cross sections
To cleavages do not intersect at 90°
Prismatic cleavage. Elongated forms that fracture a long short parallelogram cross sections
Three cleavages intersect at 90°
Cubic cleavage. Shapes made up of cubes and parts of cubes
Three cleavages do not intersect at 90°
Rhombohedral cleavage. Shapes made of rhombohedrons and parts of rhombohedrons
Forming cleavages intersect at 71° and 109° to form octagons which split along hexagon shaped surfaces many have secondary cleavages at 60° and 120°
Octahedral cleavage. Shapes made of octahedrons in parts of octahedrons
Six cleavage is intersect at 60° and 120°
Dodecahedral cleavage. Shapes made of dodecahedrons and parts of the decahedrons
Muscovite, biotite, chlorite
Basal cleavage
Plagioclase
Pyroxene
Orthoclase
Prismatic 90°
Halite
Galena
Cubic cleavage
Fluorite
Octahedral cleavage
Sphalerite
Dodecahedral cleavage
Calcite
Dolomite
Rombohedral not at 90
Amphibole
Prismatic not at 90
Quartz
No cleavage
Fracture
Any break in a mineral that does not occur along a cleavage playing is called
Conchoidal
Smooth curved fracture surfaces, like glass
Uneven
Rough irregular fracture surfaces
Hackly
Breaks along jagged services like broken metal
Splintery
Splinters like wood
Fibrous
Separates into soft fibres like cloth
Hardness
Minerals hardness is a measure of its resistance to scratching
Softest material one on hardness scale
Talc
Hardest material 10 on hardness scale
Diamond
Hard minerals
Can scratch glass but cannot be scratched with a knife blade or masonry nail
Soft minerals
Will not scratch glass but can be scratched with a knife blade or masonry nail
Tenacity
Substance resists pulling or breaking apart. Brittle, malleable, elastic or flexible
Reaction to acid
If mineral effervesces or physics or not
Hardness scale 2
Gypsum
Hardness scale three
Calcite
Hardness scale four
Fluorite
Hardness scale six
Orthoclase feldspar
Hardness scale seven
Quartz
Hardness scale eight
Topaz
Hardness scale nine
Corundum
Fingernail
Hardness 2.5
Wire nail
Hardness 4.5
Glass, masonry nail, knife blade
Hardness 5.5
Streak plate
Hardness 6.5
Striations
Straight hairline grooves on the cleavage services of Crystal faces
Magnetism
Magnetic minerals are attracted to a magnet. Such as magnetite