If you didn’t know, compounds containing metal ions emit a certain wavelength of light when heated (this depends on the arrangement of electrons), and some emit a wavelength in the visible spectrum, producing colour. For example, copper can create a blue-green flame, and potassium can produce a lilac flame.
Has there been any attempts at artificial colouration of flame colours in certain products that could be used to indicate safety certification, temperature ratings of that specific appliance/equipment, make visible to what would otherwise be colourless flames, etc.?
I know something similar is done with certain gases, colourless and odourless gases that are dangerous (flammable, toxic, etc.) are given distinctive colours and/or smell.
I was thinking more artificial fire colours (like the distinct purple fire could mean it is suitable to burn X thing, or the green fire can melt Y thing easily). I was also thinking of using colours to indicate the safety of certain fires (some fires are more dangerous than others), or to give colour to what would be colourless fires.