(IDEX Online) - Angola's diamond trading reforms have seen a steep rise in revenue, with 120 companies now eligible to buy stock that was previously available to just eight "preferential customers".Sodiam, the state-owned diamond company, says gross revenue has averaged an 8.5 per cent increase since the new trading policy was introduced in 2018. Total gross revenue for 2019 was $1.29 billion.Tax revenue for the government has also risen by 41.6 per cent as a result of the reforms. The company described the increase as "exponential growth".Under the old trading model, Sodiam sold rough stones at discount to just eight companies, with three of them - Iaxhon, Relactant and Odyssey - accounting for over half of all its diamond production.The government recognized that this was "seriously damaging the public finances," and approved reforms in July 2018.As a result, Sodiam now has more than 120 companies registered in its customer portfolio and has opened three new polishing factories.Customers submit online bids to buy rough on the company's online platform, to be assessed and agreed by Sodiam and an independent evaluator.