Minerals Flashcards
Five defining characteristics of minerals
- Naturally occurring
- Inorganic
- Solid
- Orderly crystal structure
- Definite chemical composition
Why are only 20 minerals common?
Because they are rock forming minerals that make up the Earth’s crust
How are minerals classified?
By the elements they are made of
Traits of silicate minerals
- Contain oxygen and silicon
- Most abundant group of minerals (90% of crust)
- EX: quartz, mica
Traits of non-silicate minerals
- Make up 10% of crust
- Includes some of the most important minerals
- EX: iron, copper, gold, silver, diamonds, rubies
Six classes of non-silicate minerals
Carbonates, oxides, sulfides, sulfates, halides, native elements
Carbonates
Carbon & oxygen with a positive ion, such as calcium (CaCO3)
Oxides
Metallic ion and oxygen, such as Hematite (Fe2O3)
Sulfides
Sulfur and a metal ion, such as galena (PbS)
Sulfates
Metal ion, sulfur, and oxygen (Barite BaSO4)
Halides
Elements like fluorine, chlorine, iodine, or bromine combined with a metal like sodium, potassium, or calcium, such as fluorite (CaF2)
Native elements
Single elements such as gold (Au) or silver (Ag)
Types of metallic lusters
- Surface reflection
- Metallic (shiny)
Types of non-metallic lusters
- Vitreous (glassy)
- Adamantine (diamond-like)
- Pearly (pearl- like)
- Silky (fiber-like)
- Earthy (dull)
Streak
The color of the powdered form of the mineral, that may be a different color than the material. Minerals must be softer that the streak plate
