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Literature Review
Published in Habeeb Lateef Muttashar, Sustainable Construction Materials, 2019
For centuries, garnets have been employed as gemstones. In recent times, it has been discovered that the occurrence of angular fractures, relatively high hardness and specific gravity, and the recycling ability of garnet make this material greatly advantageous for several industrial applications. Garnet can be exploited for a broad range of purposes. Usually, garnet is a generic name coined for an assemblage of complex silicate minerals with isometric crystal structures and comparable chemical compositions. The general chemical formula for garnet minerals is denoted by A3B2(SiO4)3, where A can be calcium, magnesium, ferrous iron, or manganese and B can be aluminum, chromium, ferric iron, or rarely, titanium. The six most commonly occurring garnet minerals are classified into three groups: (1) aluminum garnets, (2) iron garnets, and (3) chromium garnets. The most frequent minerals of the aluminum garnet set are almandine or almandite, grossularite, pyrope, and spessartite. The most common iron garnet mineral is andradite, and uvarovite is the most widespread chromium garnet (Krishnan, 2016).
Semi-precious stones
Published in Francis P. Gudyanga, Minerals in Africa, 2020
Uvarovite is a calcium-chromium garnet C3Cr2(SiO4)3 which is a rare garnet with a bright green colour, usually occurring as small crystals associated with chromite in kimberlites, peridotite, and serpentinite and in crystalline marbles and schists.
Origin and evolution of nephrites, diopsidites and giant diopside crystals from the contact zones of the Pounamu Ultramafics, Westland, New Zealand
Published in New Zealand Journal of Geology and Geophysics, 2023
Other granular aggregates are dominated by diopside, commonly with accessory epidote. Some specimens are banded (OU86924), with coarse vuggy diopsides in contact with finer grained diopsides in which are set idioblastic, rounded grains of a pale green, anomalously birefringent and sector-zoned uvarovite-rich garnet. Garnet grains have many fine-grained inclusions of spinel, shown by subsequent mineral analysis to comprise zincian chromite and minor chrome-magnetite. More irregular interstitial grains of garnet lack the green colour of the uvarovite and are rich in the grossular and andradite components.