Possibly a counting or prayer disc. In a previous post previous post I had argued that the total dots add up to 32, or 4 x 8, and possibly the Indus people used a base 8 system (using the thumb as counter finger but not counted itself as is still the case today). I concluded there: "Alternately, the disc and some of these counters were not used for business but for prayer, and helped their owners memorize or recite specific verses, much like rosaries today."
Dr. Kenoyer writes, of objects similar to those in the second image and specifically (c), that "bone and ivory counters with circles and lines, carved in ways that do not correspond to dice, may have been used for predicting the future," (Ancient Cities, p. 120).
This time I am focussed on the rings of 6, 11 and 15. Eleven is a prime number, and 6 and 15 are each nicely divisible by 3. There seems to be little similarity to the scale of other counters (this nearby ivory rod in the gallery has 7). Perhaps this strengthens the argument that it was a mnemonic aid, perhaps a dot for each verse of a prayer or poem.