Classification of Minerals Possibilities Chemical composition Gold Silver

Classification of Minerals Possibilities?

Chemical composition Gold, Silver, Sulfur Au, Ag, S Native elements Pyrite, Galena Sulfides Fe. S, Pb. S Hematite, Magnetite Fe 2 O 3, Fe 3 O 4 Oxides Si. O 2 Quartz, Mica, Feldspar KAl (Al. Si O )(OH, F, Cl) KAl. Si 3 O 8 Silicates 2 3 10 2

Silicates Silic- is for Silicon (s) -ate is a suffix for “oxide “ Silicates are “oxides of silicon”

Quartz Si. O 2 Silicates Mica KAl 2(Al. Si 3 O 10)(OH, F, Cl)2 Can you find the “silica” ?

Silica Structure 4 oxygen atoms for every 1 silicon atom

Olivine Pyroxenes (Augite) Amphibole (Hornblende) Micas Feldspar, Quartz Complexity Temp.

Graphite Diamond Chemical formula: C How can 2 minerals with the same composition be so different?

What’s the point here? “Internal Arrangement of Atoms” controls most physical properties!

Review of Concepts: 1. Minerals can be identified by examining…. . Physical Properties, including…. Luster, Hardness, Cleavage, Color, Streak, Density…. 2. Minerals are classified according to their…. . Chemical Composition, including groups like…. Native Elements, Sulfides, Oxides, and the all important SILICATES 3. The “Basic Building Block” of the Silicate Minerals is…. .

Review of Concepts: (continued) 4. The physical properties of minerals are generally controlled by…. . Crystalline Structure…. …or the “orderly internal arrangement of the atoms”! What do graphite and diamond have in common? …… Identical Chemical Composition…. What accounts for the differences between graphite and diamond? …. the “orderly internal arrangement of the atoms!

Quartz Muscovite Mica