Natural Hessonite Garnet Smooth Hand Polished Pear Drop Briolette Beads Strand Rondelles Sold per 6 beads & Sizes from 10mm to 11mm approx. Garnets /???rn?t/ are a group of silicate minerals that have been used since the Bronze Age as gemstones and abrasives. Garnets /???rn?t/ are a group of silicate minerals that have been used since the Bronze Age as gemstones and abrasives. The different species are pyrope, almandine, spessartine, grossular (varieties of which are hessonite or cinnamon-stone and tsavorite), uvarovite and andradite.