Set of two 19th-century crucible foundry pots - molten lava-style patina

A set of two antique foundry smelting pots dating from the nineteenth century. Likely used as some kind of crucible pot; an antique tool designed for extreme temperature applications, particularly in melting metals They are patinated by heat and lined with mixed non-ferrous metals which gives the appearance of molten lava.   

Perhaps used to melt gold or silver in a jewelry foundry. One pot features a bit of green phosphorus-like patina. Likely of European origin, possibly French. A fantastic set for textured decoration or vase for dried flowers. Note there is no drainage hole.