1. Chemical Formula: PbS Chinese Definition: 硫化铅，方铅矿

3. 1. Shape: It is like a cube, and physically, it is composed of some smaller cubic minerals. 2. Color: Most of Galena minerals are lead gray, others may be black and silvery. 3. Luster: Galena minerals have large intensity of reflected light. (It is bright and metallic!)

4. Composition: Pure Galena: 87% --Lead 13% --Sulfur Impure Galena: 87% --Lead 11.5% --Sulfur 1% --Silver 0.5% --other substances Lead is a toxic metal!

5. Hardness: 2.5-2.75 (we can scratch it with 1 coin!) Cleavage: In 3 directions

6. Magnetism: non-magnetic (Lead is non-magnetic) Streak: Lead Gray

7. Effervescence: Galena can only react with hot, dense Hydrochloric Acid (HCL).

8. Galena is a main source of industrial lead which has a wide use in many aspects such as ship’s envelope, weapons, and cables. Galena is also a semiconductor which is found use in early wireless communication systems. It was used as the crystal in crystal radio sets. But now, it is replaced by some more suitable semiconductor devices. *Interestingly, in Ancient Egypt, one of the oldest uses of Galena was as kohl, which was applied around the eyes to reduce the glare of the desert sun.

9. http://baike.baidu.com/view/82390.htm?from_id=113 20260&type=syn&fromtitle=galena&fr=aladdin http://en.wikipedia.org/wiki/Galena Earth Science 11 “Identifying Minerals” Handout