✳️Cinnabar is a toxic mercury sulfide mineral with a chemical composition of HgS.
🔷It is the only important ore of mercury. It has a bright red color that has caused people to use it as a pigment, and carve it into jewelry and ornaments for thousands of years in many parts of the world. Its bright color makes it easy to spot in the field and is a fascination for those who discover it
🔷 As a mineral ore of mercury, cinnabar is a hazardous material. It should be treated as a toxic substance. It is not a mineral to be handled or used with students. It should be stored with a label that warns unknowing people who might encounter it in your specimen cabinet, display case, or storage location
🔷 Because it is toxic, its pigment and jewelry uses have almost been discontinued.
❇️Cinnabar is a hydrothermal mineral that precipitates from ascending hot waters and vapors as they move through fractured rocks. It forms at shallow depths where temperatures are less than about 200 degrees Celsius.
🔷 It usually forms in rocks surrounding geologically recent volcanic activity but can also form near hot springs and fumaroles.
🔷Cinnabar precipitates as coatings on rock surfaces and as fracture fillings. Less often, cinnabar can be deposited in the pore spaces of sediments.
🔷It is usually massive in habit and is rarely found as well-formed crystals. Other sulfide minerals are generally found associated with cinnabar.
🔷These can include pyrite, marcasite, realgar, and stibnite. Gangue minerals associated with cinnabar include quartz, dolomite, calcite, and barite. Small droplets of liquid mercury are sometimes present on or near cinnabar.
🔷 It has a Mohs hardness of 2 to 2.5 and is very easily ground into a very fine powder. It has a specific gravity of 8.1, which is extremely high for a nonmetallic mineral.
❇️Cinnabar is the only important ore of mercury. For thousands of years, cinnabar has been mined and heated in a furnace. The mercury escapes as a vapor that can be condensed into liquid mercury.
🔹People began using cinnabar for pigments thousands of years ago in Italy, Greece, Spain, Japan, China, Turkey, and the Mayan countries of South America .
🔷Through time, people in almost every country where volcanoes are present discovered cinnabar and realized its utility as a pigment. Cinnabar is one of a very small number of minerals that was independently discovered, processed and utilized by ancient people in many parts of the world.
🔷Cinnabar was mined at the volcano, ground into a very fine powder, and then mixed with liquids to produce many types of paint.
🔹The bright red pigments known as “vermilion” and “Chinese red” were originally made from cinnabar.
🔷Cinnabar has been especially popular for making red lacquer in China. Its use in lacquer has declined because of its toxicity, but some use of cinnabar in lacquer continues.
❇️Today most, but not all, items made and sold under the name “cinnabar” have been made with less toxic and nontoxic imitation materials. Antique items made with toxic mineral cinnabar are still found in the marketplace.
🔷If you encounter an item for sale that is described or labeled as “cinnabar” you should be skeptical. If it is real cinnabar, it could be hazardous. If it is imitation cinnabar, if should be labeled as “imitation”.
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