"Wow, no one knows".... given the information you provided.
To answer: Yes, it can transfer color to your bone, ivory, ivory micarta etc. particularly if it has been dyed and has not been properly dried and buffed. A. If it has been nearly saturated with oil (a ala amateur treating the sheath with oil), or B. If it was not sealed with TanKote, or some other commercially prepared leather dressing, or Montana Pitch Bend or similar sealing product.
Most of the time it is the top residue of the dye coming off carried by excess oil and no sealer. This can also happen if an untreated home dyed piece of leather gets fairly wet.
However if The item was oiled, finished and treated by an experienced person the chance of transferring color is very slim. I don't know where you would fall in this spectrum.
Paul