Prodigal Son said:I pressure cook my bones for three to four hours too, however I stop there, no further reduction of water. For me it is sufficiently dense at that time. It is OK to cook it as you have, many cooks do this to make bouillon, or stock, freeze it in this reduced form and then re-hydrate it for sauces as and when required.
Thanks, Prodigal Son, that's good to know.