Great marbles. I have been after one of the hand-ground ones for a very long time. It seems like the older I get the further I gravitate towards non-glass marbles.
This is really interesting, Hansel - not sure I've ever seen such an application on a glass marble - a low temperature fire for decoration?
My guess is rolling.
Sorry, I couldn't stop myself. 🙂
The first three marbles are modern ones, probably from China. The next is a nice German handmade marble cut from a cane. The last one does appear to be a Marble King cross-through Cat's Eye.
Vacors are not the only marbles that show an orange peel texture on their surface but many of them, especially larger ones, do show the trait. This marble is not American and may be Vacor but it's pretty hard to tell from a single view.
I think most or all of these are not American made. Some appear to be Vacor marbles from Mexico. Others may be European or Asian.
Also, "same cane" is a term used for handmade marbles that are cut from a cane of glass. They will show pontil marks from the process.