(IDEX Online) - Indian manufacturers are working short weeks or closing their factories altogether as supplies of Russian diamonds run out.The rough supplied in normal times by Alrosa - mostly smaller stones - accounts for 40 per cent of their needs (by volume), but Surat is now feeling the full force of sanctions and banking restrictions.There will also be an inevitable knock-on effect in the US, final destination for half the diamonds polished in India, especially as the summer wedding season draws near."Small and medium-sized stones worth close to $5 billion come from Russia. They are mostly used in wedding jewellery or assembled around a centrepiece or a solitaire," Ashok Gajera, managing director of Laxmi Diamonds told Times of India."With the supply of raw materials affected deeply, most of the large factories in Surat have cut down on timings. Some are working for four days, some only three."Generic pic of diamond polishing in Surat.