Hi …. Am just wondering what could have happened here ?  The glaze has been sitting since 2018  I stirred about a week ago ( did not notice stones ) But today went to use and found these hard crystals floating on the surface The second pic is the texture of the glaze unsieved  …. The lumps are not hard I imagine even if I sieved added Epsom salts  will not be worth the risk (?) **Ps …..If I just glaze the inside of small earthenware bottles and half the outside Will they still be food safe and