Interesting! I have a friend here who collects something similar, micro slices of meteorites, and within that category there is a specific type that he goes for. He also has some very tiny pieces; all of it would fit in a shoe box, but he keeps it in a pretty antique glass-front cabinet. I'm aware about the shape of crystals being unaffected by size; years ago I led tours in the Mammoth Cave area in one of the formation caves just outside the park boundary. In particular I learned a lot about crystals when I was researching helictites, but there were lots of other shapes and mineral variations.

Regarding the proportional shapes of minerals, it was apparent in the cave, and every so often I'd have someone with vision problems on the tour.

One boy I remember in particular, he had a form of near-sightedness that apparently wasn't corrected by glasses and he brought a dim flashlight and was trying to look at the big formations; once I knew his situation I handed him my little bright spare flashlight and told him I'd point out some of my favorite tiny formations on the walls close by our path, that they are proportionately identical to the big ones 30 feet up on the ceiling. I was a trained NPS Interpretive Naturalist working in a commercial cave, so my tours were entertaining but also factual, and with each group it could change according to their interests. When you work in a private cave like that, you earn tips. The college-age kids who worked there would give a story at the end about working their way through college to get tips. My approach was to be conspicuously good at my job, and frankly, any tour that had someone with special needs was great for me. Without being obvious, but still the group knew, I would keep them beside me so I could seamlessly build in extra stops for those people, or use some trick or other to get them past any difficult spots (fear of heights, etc.)