The images you have posted are interesting. Very much understandable on how hard it is to keep the camera focused on the specimen versus the rest of the field of view. 
I recently posted a question on that subject… Photography of gemstones
With the discussion about whether or not the stone is in fact kimberlite… it could be… here is an interesting article specific to the kimberlites of the world. I was not aware of how wide-spread kimberlites are. 
Cheers!
Troy