61 Carats Swiss Blue Topaz Gemstone, Loupe Clean Topaz Cut Stone, Cushion Cut Blue Topaz Loose Gemstone, Topaz Wedding. Topaz is a silicate mineral of aluminium and fluorine with the chemical formula Al ₂ SiO ₄ (F, OH) ₂.

40 Carats Swiss Blue Topaz Gemstone, Loupe Clean Topaz Cut Stone, Cushion Cut Blue Topaz Loose Gemstone, Topaz Wedding very beautiful for Display and Collection Natural Topaz. Topaz is a silicate mineral of aluminium and fluorine with the chemical formula Al₂SiO₄(F, OH)₂.