Smithsonite ZnCO3 Carbonates

Physical Features
1. Color-White, gray, blue, green, yellow, brown, pink, and colorless.
2. Streak- White.
3. Luster- Vitreous to pearly.
4. Cleavage- Perfect rhombohedal.
5. Transparency-Translucent to opaque.
6. Fracture- Uneven to conchoidal.
7. Hardness- 4-4.5.
8. Forms- Botryoidal, rhombohedal.
9. Crystal system- Hexagonal/trigonal.
Smithsonite is a mineral ore of zinc, and occurs as a secondary mineral. Smithsonite forms in dry climates as a weathering or oxidation product of primary sulfide zinc ore deposits, and in adjacent calcarous rocks. Sometimes it occurs as replacement bodies in carbonate rocks. I think this is one of the most interesting minerals in my collection because it's botryoidal forms which has the appearance of a bunch of grapes. This is a result of radiating fibrous crystals that form attachment points, and grow outward and into each other. There are significant deposits in Tsumeb, Namibia, and talso the Broken Hill mine in Zambia. Other occurrences happen in Italy, Germany, Mexico, Australia, colorado, and New Mexico.