In stone

What are the best sellers?

There are a few lines that sell far more than the others - some fossils, some minerals.

Dinosaur teeth - a big favourite with young boys, and people who were once young boys. The site in the Kem Kem region of Morocco has led to a glut of very affordable dino teeth coming onto the market over the past decade. There are teeth from a number of species - most common are Spinosaurus, Carcharodontosaurus, Deltadromeus and Rebbachisaurus.

Sectioned ammonites - just very attractive items, and sell really just as ornaments. They're from Majunga in Madagascar, roughly 110 million years old and come in a reasonable range in sizes.

Fish - from the Green River Formation in Wyoming, they can be perfectly preserved, and again area mong the most aesthetically appealing fossils in the shop.

Shark teeth - giant megalodon teeth, little Otodus, and a few others. Appeal to the boys, again.

Minerals - it's a strange day when I don't sell a bit of chalcopyrite, amethyst, colourful calcite or fool's gold. They aren't expensive but the colours are irresistible. They look like sweets...