The Surat Diamond Association detected synthetic diamonds in a parcel belonging to two diamond traders in Varachha the world’s largest diamond cutting and polishing centre.
The parcel was sold by Ramesh Mavani a diamond merchant, who had purchased it from one Chandu Sheta.
The Natural Diamond Monitoring Committee is dealing with the investigation.
A committee was set up in 2013 after a huge quantity of synthetic diamonds was found mixed in with natural diamond parcels in Mumbai.