(IDEX Online) - India's diamond trade is bracing itself for further Covid turmoil as Maharashtra state imposes a coronavirus lockdown and Mumbai's Bharat Diamond Bourse (BDB) - the world's biggest - closes.The country is suffering an unprecedented spike in Covid infections with 103,558 positive tests yesterday, the highest total for any day since the start of the pandemic.More than half the cases are in the western state of Maharashtra, home to Mumbai and more than 110 million people.From tonight until 30 April there will be a curfew from 20:00 to 07:00 local time and a full weekend lockdown from 20:00 on Fridays until 07:00 on Mondays. Only essential businesses will be allowed to operate during this time.BDB, which was forced to shut in March 2020 as the pandemic hit, says it is closing until further notice.Surat, the cut and polish hub, is in neighboring Gujurat state and is not subject to the curfew.Pic shows a woman receiving her coronavirus vaccine in Mumbai