SULFATES Flashcards
BaSO4
Barite
Orthorhombic crystals usually tabular on {001}. Crystals may be very complex. Frequently in divergent groups or tabular crystals forming “crested” or “roses.”
Barite
Cleavage is pinacoidal perfect to prismatic less perfect
Barite
The hardness of barite is __________.
3 - 3.5
It has a specific gravity of 4.5
Barite
What are the usual color of barite
Colorless, white, and light shades of blue, yellow, red.
Occurs most commonly in hydrothermal veins associated with ores of silver, lead, copper, cobalt, and manganese.
Barite
SrSO4
Celestite
Orthorhombic crystals closely resemble those of barite. Commonly tabular on {001} or prismatic parallel to the a or b axis.
Celestite
It has a basal perfect and prismatic good
Celestite
Celestite has a hardness of _________
3 - 3.5
It has a specific gravity of 3.95 - 3.97
Celestite
The celestite has a common color of
Colorless, white, often faintly blue or red.
Most commonly as disseminations through limestone or sandstone, or in nests and lining cavities in such rocks. Associated with calcite, dolomite, gypsum, halite, sulfur, and fluorite.
Celestite
PbSO4
Angelsite
Orthorhombic crystals with habit similar to that of barite but more varied. Also massive, granular to compact.
Anglesite
It has a cleavage of basal, prismatic imperfect. fracture conchoidal.
Anglesite
Anglesite has a usual hardness of ________.
3
It has a specific gravity of 6.2 - 6.4
Anglesite
Anglesite has a usual color of ___________.
Colorless, white, gray, pale shades of yellow. May be colored dark gray by impurities
A common supergene mineral found in the oxidized portions of lead deposits. Associated with galena, cerussite, sphalerite, smithsonite, hemimorphite, and iron oxides.
Anglesite
CaSO4
Anhydrite
Orthorhombic but rarely in crystals. Usually massive or in crystalline masses resembling an isometric mineral with cubic cleavage.
Anhydrite
Anhydrite has a cleavage of _________.
Three pinacoidal cleavages
Anhydrite has a hardness of ________.
3 - 3.5
Anhydrite has a specific gravity of ___________.
2.89 - 2.98
What are the usual color of anhydrite?
Colorless to bluish or violet. May also be white or tinged with rose, red, or brown.
Is found in much the same manner as gypsum, with which it is commonly associated, but is less common than gypsum. Occurs in beds associated with salt deposits in the cap rock of salt domes, and in limestones.
Anhydrite
CaSO4·2H2O
Gypsum
Monoclinic crystals of simple habit. Commonly tabular on {010}; diamond-shaped with beveled edges. Twinning on {100} common, resulting in swallowtail twins.
Gypsum
What is the hardness of gypsum?
2
What is the specific gravity of gypsum?
2.32
What are the usual colors of gypsum?
Colorless, white, gray; various shades of yellow, red, brown, from impurities
___________ is a fibrous gypsum with silky luster.
Satin spar
_________ is a fine-grained massive variety.
Alabaster
_______ is a variety that yields broad, colorless, and transparent cleavage folia.
Selenite
Commonly distributed in sedimentary rocks, often as thick beds. Occurs interstratified with limestone and shale and as a layer underlying beds of rock salt.
Gypsum
