An interesting Galena Quartz combo. Shiny cubes of Galena with Quartz Crystals on matrix. Start or add to your metals collection with a specimen from a premier location.
4.5cm x 4cm x 1.8cm, 20g.
Ninth of September Mine, Madan, Bulgaria.
Galena is a common and popular mineral for rock hounds. Its characteristic cubes, distinctive cleavage and high density make it easy to identify. The structure of Galena is identical to that of halite, NaCl. The two minerals have the same crystal shapes, symmetry and cleavage. Some Galena may contain up to 20% silver in place of lead.
One of the first transistors was a Galena Crystal and with a copper wire called “cats-whisker-with crystal”. Galena is a natural semiconductor. Really it formed part of a transistor, a more reliable PN junction or Diode. Metal Sulfides form natural PN Junctions like copper and copper oxide which also formed one of the first solar panels. Such an interesting subject I could on on about it.
Galena is the primary ore mineral of lead and and ore of Silver. Worked for its lead content as early as 3000 BC. Found in ore veins with sphalerite, pyrite, chalcopyrite, tennantite-tetrahedrite and skarns. Also found in sedimentary rocks where it replaces carbonate beds or deposites in pore spaces. The crystals are bright when fresh but often tarnish when people touch them. Lead sulfide may contain impurities, such as silver, arsenic, antimony, and copper.
Quartz is one of the most common minerals found in the Earth’s crust. If pure, quartz forms colourless, transparent and very hard crystals with a glass like luster. Today it leads technology being the main component of transistors which make our computers work and solar panels.