Mineral Set 5 Questions Flashcards
What is Celestite and how does it relate to Barite?
Clestite is part of the Barite group and is Isostructural to Barite, meaning it has the same crystal structure but not the same composition. Celestite is SrSO4, while Barite is BaSO4.
Alabaster and Seleneite are varieties of what mineral?
Gypsum.
Which is harder, gypsum or fingernail?
Fingernail
When heated, gypsum loses water to become what mineral?
CaSO4*2H20, when it loses water it becomes Anhydrite.
Turquoise, Malachite and Chrysocolla are all copper bearing minerals and a greenish colour. What physical test could distinguish these minerals?
Turquoise is hard, Chrysocolla can adhere to your finger, and Malachite can react with HCL.
Corundum and which two minerals constitute the haematite group?
Corundum, Haematite and ilmenite
How are ruby and sapphire related? What causes the colour difference between them?
Ruby and sapphire are both corundum. The RED colour of Ruby comes from Cr impurities, while the BLUE colour of Sapphire comes from Fe and Ti.
How is appetite distinguished from Beryl?
Crystal Form: Apatite = pyramidal terminations; Beryl= Pinacoid terminations.
Hardness: Apatite = lower hardness (5), while Beryl is harder (7.5-8)
Limonite occurs in the same general environment as Geothite. What environment is it?
Limonite and Geothite are produced by weathering and hydrothermal alteration of Fe-bearing minerals.
They usually occur as waste minerals in ore deposits.
Is Limonite a mineral? What is it?
Limonite is not a mineral. It is an amorphous susbtance.
An “amorphous solid” is any substance (Not crystalline) that lacks a long-range order that is characteristic of a crystal.
What is the most common environment of formation for Graphite?
Graphite forms decomposition of organic material that was deposited in sediments.
It is common in Pelitic metamorphic rocks (Phyllite, Slate, schist), but can also be found in oragnic-rich shales and coal beds.
What is the environment of formation of Wulfenite?
Wulfenite is a secondary lead mineral that forms in the oxidized zones of hydrothermal lead deposits
What is the environment of formation for Scheelite?
Scheelite is found in skarn deposits formed by contact metamorphism of limestones adjacent to granitic intrusions.
Plus hydrothermal veins and greisen.
