Diamond prices opened a touch lower from last week’s year high in quiet trading volumes.

The main PolishedPrices index, which tracks all sizes between 0.3 carats and 3 carats, opened 0.9% lower at 128.4 points. This is 3.9% above its level of this time last year and 2.4% higher on the year so far.

Most Commercial and Mixed qualities were in negative territory. However, Fine one carat diamonds continued to strengthen, gaining 4.5% on the week.

The definitions of groupings are:

Fine: goods better than I colour and VS2 and above.
Commercial: K SI3 and above, excluding the Fine category,and
Mixed: the rest down to M I3