(IDEX Online) - Manufacturers will increasingly turn to lab growns to fill supply gaps caused by sanctions against Russia.Botswana's minister of minerals and energy, Lefoko Moagi, told a mining conference it would be hard to source enough natural diamonds to replace Alrosa's missing output."We see the 30 per cent gap that will be left by the ban being plugged by something else that is not natural. And for us that will be a challenge," he said.The ban on Russia diamonds could force prices up but rival miners are anxious about ramping up production - which is an expensive and time-consuming move - especially if the war ends, sanctions are lifted and Alrosa starts selling again.The preferred option for Indian manufacturers is to use lab growns, especially for smaller sizes - under 0.30-cts - where supplies have been particularly affected by sanctions.Jacob Thamage, head of Botswana's Diamond Hub, told Reuters: "You don't want to invest a lot of money to up-scale and then the war ends the next day."He said higher prices were pushing consumers from mined towards lab grown diamonds.Pic shows diamond polishing in Surat, India.