This is an International Gemological Institute (IGI) Colored Stone Report for a natural tanzanite gemstone. The report certifies that the gemstone is a natural zoisite (tanzanite variety) weighing 23.37 carats, cut in a square emerald mixed cut, and measuring 17.17 × 14.04 × 10.35 mm. It is described as bluish violet, transparent, with natural characteristics, and is classified as having Tanzania origin based on current gemological information. The report also includes the gemstone's optical properties, an approximate photograph, and notes that while tanzanites are commonly heat-treated, no indicative evidence of treatment was observed.