Fig. 3

Transmission electron micrographs of paste calcinosis (a & b) and stone calcinosis (c & d) particulates. The recorded images reveal the difference in morphologies of the two samples. The paste sample contained needle-like crystals with tapered ends while the stone sample is composed of rounded particles. The hydroxyapatite crystals in the deposits therefore display very different morphologies, where this may be indicative of different stages of the calcium deposit formation