(IDEX Online) - The businessman who launched the Cofix chain of no-nonsense coffee shops in Israel is now moving into lab-grown diamonds.Avi Katz has just opened the first X Lab Diamonds store at a mall near Tel Aviv and plans a roll-out to London and Moscow, as well as more locations within Israel.His introduction in 2013 of a fixed five-shekel ($1.50) price for coffee and a range of other drinks and snacks disrupted the market, forcing rivals to lower their prices. Now he's moving into lab-grown diamonds, saying they'll sell for around half the price of comparable mined equivalents.A one-carat solitaire ring, set in 18k white gold, is priced on the website at just over $2,000.Katz, a serial entrepreneur, told The Jerusalem Post he'd attracted almost $6m from backers and was importing diamonds from Hong Kong and India.He went on to sell 80 per cent of his stake in Cofix, which had 145 outlets in Israel and 135 in Russia.Pic shows flagship X Lab Diamonds store