If you don't believe everyone here you can call S&W and check. However, the dealers are certainly aware of what they're made of and have advertised them as such. Also, the 13.3oz weight and two piece/shrouded barrels are give aways.How do we know these are Scandium alloy? I don't recall any markings to that tune.
The earlier carbon steel cyl runs had the cyls finished in dull blue, similar to the 586 L-Comp. It was a thin, cheaply done finish and the cyls were very susceptible to surface rust, that's why I had Robar coat my cyl with NP3. The later SS cyls have the melonite coating.Melonite is an incredible finish...definitely not something that would turn me off based on the "goofiness" of the name. In contrast, I would be much more inclined to buy something with a melonite finish than not.