It’s hard to see from the pic, but are those bubbles inside the stone, or are they small notches or divots on the surface of the stone?
The reason I ask is that many ancient gemstones have such notches/divots, and a couple things suggest those stones were worked a long time ago (when considered together): the source location (especially if these are from the Khmer/highland regions of Thailand, the slight variation of hue in the band of faceting around the base of the stone, and the faceting style. Of course, it’s hard to tell without looking at them closely and for some time, and old stones are regularly treated or further worked in modern times, but if ancient, these features would be normal.
If you’d like to see other examples please PM me and I can share several of different types of stones all of which exhibit similar features.