These topaz crystals are from the Mogok Township, Pyin-Oo-Lwin District, Mandalay Region, Myanmar. The alluvial deposits in this area produce over 100 different minerals including several gemstones like topaz. It is a silicate that contains the elements Al, Si, O, F and H. This is a small cluster of up to 4 crystals. They are mostly transparent with some internal flawing. They are colorless and have a glass luster. These topaz crystals measure approximately 1 9/16 x 1 3/8 x 1 3/4 inches or 40 x 35 x 45 mm. It weighs 425 carats.