Iron Pyrite

This is one of a few crystals that I've obtained recently, it is iron pyrite, also known as fools gold. It has the most amazing crystalline state that can create these interlocking cubes. Each of these, not quite perfect, cubes is about the size of a large die - but the density is quite impressive - and, aside from the slightly auric tint is probably what gives it it's common name.

This particular image is an experiment ( which wasn't  quite successful ) in focus stacking. This is done by taking a number of images each with a slightly different focus point and then letting Photoshop do all the monkey work to combine them into an image that is sharp front to back. This is my first proper attempt, and combined about 25 distinct images to form this single one. I can see the flaws where they've not combined properly ( as I have the real thing to compare it against ! ), and I suspect that given more time it may be possible to resolve this by manually masking / aligning the various layers. 

The clearest example for me is if you look at the left most cube on the top edge on the left, it appears to be chamfered, this is - in fact - a single sharp edge and the misalignment of a photo in the stack has caused PS to think that this is a legitimate interpretation ...

This did, however, take me nearly an hour to do to get this far, and I'm going to chalk it up as a learning experience, and be more careful in shooting / choosing the source material ( these were all hand held, rather than on a tripod ) so as not to introduce such errors.