I think you could get what you want by having a jeweler cut the gems where it gets thinner in some spots and overlay them, like where you want the sapphire to show most is where the thickest part of sapphire with an asbense of amethyst overlay is and vice versa for amethyst, everything between would be in a gradient as they overlap in those parts.
I imagine the gems being cut almost like a ying yang, each side being the pure stone and the middle having a mixture of colors from where the stones overlap.
I know this isn’t answering your question about melting but I think it’s the easiest way to get the ring you want.
Thisbutbetter t1_j6d2n6y wrote
Reply to can gemstones be melted into a gradient? by Acceptable_Shift_247
I think you could get what you want by having a jeweler cut the gems where it gets thinner in some spots and overlay them, like where you want the sapphire to show most is where the thickest part of sapphire with an asbense of amethyst overlay is and vice versa for amethyst, everything between would be in a gradient as they overlap in those parts.
I imagine the gems being cut almost like a ying yang, each side being the pure stone and the middle having a mixture of colors from where the stones overlap.
I know this isn’t answering your question about melting but I think it’s the easiest way to get the ring you want.