You are correct, Jamey, about the word reconstituted being used in this context. "Recon" or reconstituted is probably more common than reconstructed. But, as you say, it is even less correct. My prevoious post probably should have used the word "reconstituted" as that is the common use.

Much of what I see called reconstituted amber appears to be small chunks of amber suspended in an amber colored resin. It's fairly common from Russian sources. Sometime there are only "sun spangle" sort of flakes floating in the amber colored resin. I suspect that may be entirely man made.

The reason I don't think much magnesite is used in a reconstructed or compressed nugget form is that it takes a dye quite nicely and is relatively hard. There is not much need to make blocks of magnesite material. (although , at the bottom of the picture of blocks of stone you can see some pink stuff that is very similar to the pink dyed magnesite. At a glance it didn't have any "grain" do I assumed it to be entirely man made.)

I could be way off base about magnesite not being ground up, reformed, dyed and stabilized. It could easily be the material for some of the so called carved beads in this material. They would be molded instead of carved. (Or "CAVED" as it is often spelled in China.)