Automated sorting and grading system for Tanzanite employed at mine

TanzaniteOne has begun using an automated rough tanzanite optical sorting and primary grading system, installed at the company’s Merelani Tanzanite Mine in Northern Tanzania. It is the first type of system ever used in the colored gemstone industry and is seen as a significant technological milestone in TanzaniteOne’s drive to continuously improve recoveries and efficiencies, the company said in a statement.

The company, which is the world’s leading miner and marketer of tanzanite, said the system achieved a tanzanite recovery rate of between 96% and 100%.

Following primary sorting of rough tanzanite by the system, TanzaniteOne has pioneered a secondary sort run to select broad grades of rough tanzanite in a completely hands off environment, the company said. Differential testing, to determine the accuracy and efficiency of the optical sorter, has produced “highly satisfactory results,” with the entire operation managed and monitored electronically from an off-site location.

“The installation and commissioning of this optical sorting system allows us to significantly improve the efficiency and grade of tanzanite production while reducing processing time and costs,” said Ian Harebottle, president and COO of TanzaniteOne. “We aim to significantly increase throughput capacity at our Merelani Tanzanite Mine and enhance the profitability of our existing tanzanite operations, whilst simultaneously freeing up further capacity for future expansion.”