Thursday, February 16, 2017

Pietersite

Also known as "Tempest Stone".   Breccaited is your word for this week.  It comes from the Italian word for "loose gravel".  Brecca refers to any rock that is composed of broken fragments of other rocks that then meld together.  Pietersite is made up of pieces of golden tiger's eye and blue hawk's eye cemented together by quartz.   As w/ many geological formations, this one also is controversial.  Some geologists say it is not a tiger's eye/hawk's eye blend but a chalcedony embedded w/ amphibole fibres which gives it the chatoyancy (remember that was the word from last week).  The conflict could be caused because there are two places mining Pietersite.   This rock came from a mine in the Kunene region of Namibia.  The other site for Pietersite is in Hunan, China (that mine became flooded and hasn't been operational for years).  The rocks from the two sites vary a little in composition.  It has a hardness of 7.

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