This piece is a great example of how amethyst forms here in Scotland. It comes from the hills in the south, down in Dumfriesshire and Galloway. Well, it does when it looks like this.
I don't fully understand the geology behind this but I am working on it. The amethyst grows on this jagged base which is an epimorph of dolomite after calcite, or something similar. What you end up with is square shaped, jagged, pointed, squashed amethyst.
These two Druzy pieces got smushed together so that they look like teeth. There is a little limonite staining in there too, so it's a pale purple and yellowish colour. It's not real citrine, but it's the closest I've found in Scotland.