Wednesday, December 5, 2007

More on Red and Yellow Ocher (Ochre)

Recently I had posted a request for people to submit their thoughts on the existence of red and yellow ocher in burials in our area.

to read that article - - click here.

I just received this commentary and thought it was interesting and wanted to share it...I really had never considered the fact that ocher colors could have been manipulated.

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"Hematite is a mineral in the hematite group. They are trigonal, metallic oxides,and are composed of one or more metals and oxygen, and resemble each other structurally. Corundum (Aluminum oxide), Eskolaite (Chromium oxide) and Karelianite (Vanadium oxide) are also in the Hematite group. Hematite is the primary ore of iron.

Hematite occurs in many different habits, including numerous crystal forms, massive, and earthy, which is called ocher.

Ocher (ochre) occurs in 4 major forms. Yellow ocher is hydrated iron oxide. When yellow ocher is heated, driving off the water, it turns red. Both occur naturally, but the red ocher found with other artifacts, could have been "made" by the people who used it. Red ocher can also be purple, due to particle size. There is also brown ochre, which is partially hydrated iron oxide and is more commonly known as common rust. There are other colors, such as grey or orange, etc., all with their own names, and resulting from different amounts of water.

There would have been little native hematite in the valley area, except for glacial deposits, trade pieces, or very small amounts obtained from "rusted" pyrite (iron sulfide) that occurs sporadically in some sedimentary rocks, as in the pyritized fossils found in western NY."

- Don M.(SRAC member)

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