Huge emerald and tanzanite gemstones go under the hammer in Washington

As we've reported, US Asset Forfeiture and Seizures will be offering over 550 lots of collectibles this weekend including a 1950 Packard Victoria Super Deluxe.

Whilst that is a genuine find, and no doubt the most exciting lot for classic car collectors, we have rather been holding back on telling you about the most exciting and valuable lots on offer.

These are some truly extraordinary pieces of investment-grade jewellery, including an extraordinary range of tanzanite gems.

Large beautiful tanzanite

The only known deposit of tanzanite is a five square mile hilltop at Merelani Hills near Ausha, ten miles south of the Kilimanjaro International Airport in Tanzania. Tanzanite gained worldwide fame as a fine and rare gemstone in itself.

Tanzanites in especially good qualities and larger sizes are in serious demand and command high prices. It isn't only the spectacular colour. Since the stone is found in only one special location in the entire world, it is especially rare.

There are several available in the sale priced at up to $65,000. However these are not the likely top lots.

Extraordinary natural emerald

That honour is likely to go to one of two lots: a 5.38ct cushion-cut white diamond and yellow diamond framed platinum ring or a huge 1299ct emerald gemstone, the latter being a GIA appraised natural earth-mined gemstone.

These are going under the hammer with estimates of $125,000-$175,000 and $100,000-$183,000 respectively on March 26^th in Washington State, USA and online.