I haven't had any girrafe bones to do but I have done bisson and moose leg bones in slowly boiling water with Rit dye.I first cleaned the bones after sizing them down some,by boiling in a solution of T.S.P. several times if necessary. Never try to dry the bone scales in an oven afterwards thinking you will get moisture out, they will crack . The Rit seems to replace any moisture that was in the bone. You can get some strange colors however. Browm will get you a purple, navy blue gives a lovely blue color, crimson gives a good scarlet color. Leather dyes can work well too after the scales are sized down. Do not hesitate to use more than one coat and more than one color. The results can look like mammoth ivory and I hear that the giraffe bones are being done to look this way commercially. frank