Please read the essay posted here related to "Pyu" beads from Burma. This demonstrates that the technology for making chemically-decorated beads was very likely transferred from India to Burma, some 2000 (+) years ago. (Now, I would follow protocol and refer to these as Tircul beads.)

You have a bead that is brighter red, and has dark gray lines. This is what Beck called a "Type III" carnelian bead. ("Black on red."). If this is the bead you think might be coral, it is not coral. The chemical decoration process would not be successful on organic materials; nor on practically any minerals apart from agate.

All of your beads were probably made in India. However, Burma cannot be entirely ruled-out.

JDA.