Ian, Going back to the original question about value, there is a huge disparity in value of tektites depending on how prolific they are in their strewn field. From the most abundant fields, like China and Thailand, one can buy quite large ones at the big wholesale shows for as little as $10 each. From strewnfields where tektites are scarce and hard to get, like Georgia, USA, they aren't often seen for sale and even tiny ones can cost $100 or more. Australian ones are likely to be somewhere inbetween in value, although I'm certainly no tektite specialist, so this is just a very vague opinion. Although tektites aren't really meteorites, they tend to attract the same aficionados as meteorites, and it is the meteorite dealers who sell most of them, so check out some meteorite dealer websites for better info on prices and buyers.
Shape influences price too. Some of the more classic aerodynamic shapes, like flanged buttons for example, bring much higher prices than the more ordinary blobs.
