To date, there are no published data elaborating on the manner and/or rate in which gastrolith chitin layers are formed. In any case, it is a continuous process that requires fast maturation of each newly formed stratum while the next is already being secreted and, therefore, is likely to involve a set of hardening factors working in concert, including converted hemocyanins. Indeed, we found that our gastrolith hemocyanins can function as phenoloxidases in the presence of SDS,
as was shown previously (Adachi et al., 2005) for cuticular hemocyanins.