Chicken Stock gelatinous I made chicken stock recently from chicken thigh bones and skin (just needed the thigh meat and the bone-in-with-skin were cheaper).  After cooling it in the fridge I ended up with gelatinous semisolid stuff underneath a layer of fat a few mm thick.  I removed the fat, but am wondering whether the "stock" underneath it is useable for anything.
This is normal, expected, and desired.   The long simmering of the bones will dissolve collagen in the connective tissue, creating gelatin, which will cause it to quite literally gel when cooled.

This gives the stock a body and texture that is considered a virtue in using it for soup or as an ingredient in other recipes.  When heated, the gelatin will melt again.