(IDEX Online) - A small-scale miner unearthed over 5.2kg (11lbs 8oz) of Tanzanite - one of the world's rarest gemstones - making him an overnight millionaire.It is found only in a four-mile strip of Tanzania, near the Mererani Hills in the north of the country.Anselim Kawishe found two stones, with a combined 5.2kg weight, after 15 years of searching."I did not expect that there will be a day when I will be standing here carrying such a big Tanzanite gem," he said according to a report in African Mining Market.Adolf Ndunguru, of the Ministry of Minerals, said they were worth $1m.Tiffany & Co first marketed the green, red, purple and blue stone in 1968 under the name Tanzanite, after Tanzania, rather than blue-violet zoisite, its scientific name.In June 2020, Saniniu Laizer, 52, a farmer and part-time miner, sold two Tanzanite slabs weighing 14kg (31lbs) for $3.4m.He said he'd use some of the proceeds to build a school and shopping mall for his community. He has four wives, 2,000 cows and a license to mine for Tanzanite in an area that is now protected by a perimeter wall to deter illegals.File pic shows Saniniu Laizer with his Tanzanite.