BRASS-- some more research.
Brass is an alloy of COPPER and ZINC.
Beta brasses can only be worked hot, and are harder, stronger, and suitable for casting. The high zinc-low copper content means these are some of the brightest and least-golden of the common brasses...
https://en.wikipedia.org/wiki/Brass
..“golden copper” which became the standard term for brass.[49]
…Brass was produced by the cementation process where copper and zinc ore are heated together until zinc vapor is produced which reacts with copper….
https://en.wikipedia.org/wiki/Brass
So when brass is worked hot or burned, it doesn't turn black but there came about a big market in 'black brass' which the internet sites provide a lot of information about in regards to solutions used like ammonia or some said palmolive oil and etc. to turn it black.
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Bronze and brass can be made to look weathered by soaking the part in a solution of water and ammonia. At first the color will be a dull tarnished-brown appearance. If left long enough (two or three days) the surface will turn to a green patina…
…Torch brass and spray ammonia on it
Rub with a mixture of salt and vinegar and then expose to ammonia fumes for hours/days. A blue crust will form and under this will be the green verdigris surface on the brass. I tried some of the brass blackening compound a few years back when I lived in AZ. It turns brass quite black, a bit splotchy, and is not durable.
http://www.practicalmachinist.com/vb/gunsmithing/what-turns-brass-black-126807/
Anyway, I do think that there is such a thing as a certain metal alloy that do look black without soaking in solutions.
Well Brother, I'm not a chemist, but my husband is a chemist, so I will share with him. At any rate, i do believe that Brass IS DEFINITELY A DARK COLOR to be sure. I still think that if the word phrase is 'brass that is burned' means that it is made to glow, but not necesarrily [sp?] turn black.
Fine brass burned in a furnace means to me 'purified brass' but again, the color would definitely be 'a dark color'. I'm thinking 'black brass', I don't know about that. I did show a brief youtube of someone diffing brass in some solution and it turned black, but i don't even think that was like 'a permanent black color'. But, I will think about what you wrote. Thank you!