The Treasury, run by the regional government, displays the spectacular gemstones and gold dredged out of the Sakha Republic's mines. The diamond collection is the heart of it, but the gold and mammoth-ivory items are also remarkable.
You go through with a guide who explains how the diamonds are sorted and cut, and there is a small exhibit of historical Yakut jewellery using mammoth tusk and silver. Visits often need to be arranged in advance — check with your hotel.