Christmas present for a gem enthusiast?

My younger brother is very into 💎 he goes out into nature and finds different gemstones and has recently been attempting to cut and facet them. Aquamarine, Emerald mostly I think he sometimes has found ruby. I think he probably has most everything he needs to do this hobby but is there anything gem enthusiasts need on a regular basis or they find helps then the most when it comes to this hobby? If you could get something for Christmas related to this hobby what would it be?

Thank you