Up to the second quarter of the eighteenth century the only known sources of uncut diamonds were India and, to a lesser extent, Borneo. Indian diamonds had been earlier known in the Mediterranean world 1 but a regular export trade had begun only as a result of the intensification of trade between India and Europe in the sixteenth century. 2 Although transport by sea was not, for the diamond trade, such an overwhelming advantage as it was for heavier goods, it gave an important stimulus to the trade by reducing the risk of the voyages. At the same time the diamond industry developed in Europe. It was first centred in Antwerp, but shifted to Amsterdam in the seventeenth century. New methods of cutting and polishing were evolved, and it was not long before Indian diamonds were being sent back to their country of origin after having been cut and polished in Europe. 3 Italy and Portugal were also early centres 4 and in both Jews apparently played an important role as lapidaries and jewel merchants. The Portuguese, as the pioneers of the European trade with India, were the first to import diamonds by the new sea route. The French traveller Tavenier, who was something of an expert on diamonds, stated in the 1660s that Goa had formerly been the great centre of the diamond trade. 5 This seems to show that others had already become dominant in the trade during the first half of the seventeenth century, a trend which is also reflected in the papers of the English East India Company.
The East India Company endeavoured from the very first to gain a foothold in the diamond trade with the East. The English had some success, despite sharp competition from the Dutch both in Borneo and in India, and in the years 1615-21 there was a regular trade in Borneo stones which were sold in public sales held by the East India Company in London. 6 The Company also encouraged its agents at Masulipatam to buy stones, but they were hampered by lack of means and by the monopolization of the trade by the Dutch. In April 1632 the English agents reported to London that the Dutch had established themselves near the