Mica KAI2(AISi3)O10(OH,F)2 Silicate Group

Physical Features

1. Color- Colorless to pale yellow.

2. Streak- White.

3. Luster- Pearly.

4. Cleavage- Perfect.

5. Transparency- Transparent in thin layers.

6. Fracture- Even.

7. Hardness- 2 to 4.

8. Forms- Poorly crystalized.

There are 37 different mica minerals, all in which have crystalline structure that forms layers that can be split into thin sheets. Chemically they contain complex silicates of aluminium and alkalies with hydroxyl. Some varieties may contain iron, magnesium, and lithium. Mica can be found in pegmatites which are widely distributed and occurs in igneous, metamorphic and sedimentary rocks (granite). Mica pegmatite consists of a quartz core with feldspar sides. There are seven important mica minerals. Starting with the most popular of the group. 1. Muscovite, 2. Paragonite, 3. Lepidolite, 4. Phlogopite, 5. Biotite, 6. Zinnualdite, 7. Lepidomelane. Mica occurs all over the world.

Chrysocolla (CuAI) 2H2Si2O5(OH)4nH2O Silicates/phyllosilicates

Physical Features
1. Color- Blue, blue-green.
2. Streak- Pale blue, tan, gray.
3. Luster- Vitreousto earthy.
4. Cleavage- None.
5. Transparency- Transparent to nearly opaque.
6. Fracture- Uneven to conchoidal.
7. Hardness- 2-4.
8. Forms- Massive.
9. Crystal systems- Orthorombic.
Chrysocolla is a mineral that is made from hydrated copper silicate. It most commonly forms in the oxidation zones of copper ore bodies. Many times chrysocolla is associated with other minerals, such as quartz, limonite, azurite, malachite and cuprite, which are frequently intergrown together. Typically found as glassy botryoidal or rounded masses and crusts, or vein fillings. Chrysocolla is sometimes confused with turquoise because of it's light color. Some say it's used for inspiration or creativity, and may help to promote communication.

Jet Organics/ Hydrocarbons

Physical Features

1. Color- Black, brown.

2. Streak- Black to dark brown.

3. Luster- Velvety to waxy.

4. Cleavage- None.

5. Transparency- Opaque.

6. Fracture- Conchoidal.

7. Hardness- 2.5.

8. Forms- Amorphous.

Jet has been classified as a coal because of it's high carbon content. Jet is a fossil wood belived to have formed as a result of being waterlogged and then buried in oxygen deprived mud of the ocean floor for millions of years. Today Jet occurrences can be found in sedimentary marine rocks all over the world. Just the other day when digging in my garden I came across a real nice piece, and of course I saved it. Maybe one day, i'll use it in a ring. Jet is well known for it's amazing uses as an ornamental, such as jewlery.