void main()
{
    object oPC = GetLastUsedBy();
    object oStone = GetFirstItemInInventory(OBJECT_SELF);
    object oAnotherItem = GetNextItemInInventory(OBJECT_SELF);
    object oAnvil = GetNearestObjectByTag("NK_FP_ANVIL", OBJECT_SELF, 1);
    string sStoneTag = GetTag(oStone);

        if ((oStone != OBJECT_INVALID) && (oAnotherItem == OBJECT_INVALID))
            {
            SetLocalString(oAnvil, "STONE", sStoneTag);
            }
        else
            {
            SetLocalString(oAnvil, "STONE", "invalid");
            }
}