Talk:Uvarovite
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Uvarovite dose not tracer mineral in the search for diamonds because it dose not commonly occurs with diamond in kimberlite pipes.
Commonly occurs with diamond in kimberlite pipes pyrope, with hight Knoringit content - red garnet. for example see: http://www.amnh.org/exhibitions/diamonds/indicator.html
Stepanovas 12:01, 11 May 2005 (UTC)
- Both uvarovite and knorringite (high Cr pyrope) are used as kimberlite indicator mins. Vsmith 17:09, 11 May 2005 (UTC)
As I put on the diamond talk page, I tend to agree that Uvarovite isn't a common indicator for garnets (but chromian pyrope and knorringite are). There has been a lot of misuse of the term 'uvarovite' to cover any chromian garnet, many old references carry this error, and claim 'uvarovite' from all sorts of places. Most such samples tested have been proven NOT to be uvarovite, but to be either pyropes or grossulars. Uvarovite itself is a rare mineral really restricted to metamorphosed ultrabasic rocks where there has been some mechanism for the input of calcium ions during the alteration process, such as at Sarany in the Urals, and in northern Finland. --Jolyonralph 23:11, 11 May 2005 (UTC)
Uvarovit never used for searching kimberlites. I know it because I familiar with diamond prospectors and had been at diamond deposits, and searched diamonds by myself.
Diamonds searched by red as blood garnets. Green garnet in kimberlites are rare and usually are not uvarovit(I agree with Jolyonralph).
But question is not so easy. Any garnet from kimberilit contain Ca, Fe, Mg and Al , Cr (Si of course). So garnets may be considered as mixture of Uvarovite -Ca3Cr2(SiO4)3 and Pyrope - Mg3Al2(SiO4)3, but same way it may be considered as mixture of Grossularite - Ca3Al2(SiO4)3 and Knorringite Mg3Cr2(SiO4)3. Haw we should name nature garnet with difficult composition? For solving this question we must determin content of pure components Uvarovite, Pyrope et. al. In Russian mineralogy exist term minal. It is pure components in mineral which once dose not exist. Composition of mineral may be evaluated different ways. Depending on method we may to receive different minals content. Determination of minals content very important in thermodynamic geochemistry.
Stepanovas 05:10, 12 May 2005 (UTC)