What did you do to try to determine whether the stone was dyed? What was your "dye test"?

If you are willing to sacrifice a bead, I suggest splitting it in two. You can probably accomplish this by using a thick steel needle that can be inserted into the perforation, but does penetrate all the way through. Set the bead and needle on a firm surface (needle pointing down; on wood is good), and hammer the needle into the bead. It will probably split into two or three pieces.

As mentioned, dye penetration in howlite is typically superficial, and is white inside. Natural matrix will be apparent in the interior.

In contrast, magnesite imitations routinely have very good dye penetration, and color the entire mass. However, magnesite imitations often have superficial crackling (the point being to imitate a spiderweb appearance, I suppose); and they often have some sort of discoloration process (brown) that imitates matrix. Both of these may be present—or it could be one but not the other. These are notably superficial affectations—and (in my experience) do not penetrat deeply into the stone. So this is different from the actual matrix of turquoise or howlite, that is also internal.

Please tell us what you determine. Jamey