Ice block

Created in a Tub at (TBD height) high altitude. Available at night time (6pm-6am). Add 20 water to tub, wait for it to evaporate.

Ice Block in inventory melts at 10am give or take a couple of minutes. Placing 2 blocks in a chest does not melt at 10am, adding more blocks makes the chest a refrigerator. Have had 10-11 blocks in the chest for several days and it seems to keep jugs of milk longer.