All of us have seen fire burning. Fire emits light of its own, and the colors we associate with fire are colors such as red, yellow, orange, and blue. Additionally, when a regular light beam is directed at a regular fire, it will go right through it, so fire is not an entity that casts a shadow. In the video below, James Orgill from the YouTube Channel The Action Lab manipulates the lighting and the material burning in the fire to produce black fire, a fire that absorbs light and casts a shadow!
I have posted in this blog about how the chemical and physical characteristics of an element can be dramatically altered by other elements with which it combines. A case in point is sodium chloride (table salt), which is an innocuous chemical. However, as the video from the BackyardScientist below demonstrates, molten sodium chloride can be quite explosive when added to water. However, this reaction seems to be a physical reaction not related to the explosive properties of elemental sodium. It may have to do with the way the water is heated and converted to vapor very fast within the blob of the molten salt as it goes under the surface of the water.