5th Century Greek shipwreck

[Imperial Dave]

https://greekreporter.com/2024/10/04/ancient-greek-shipwreck-atlantis-metal-recovered/

A new one on me...

[Ian61]

Brass is an underappreciated metal even today, it's value to science through the apparatus made from it has been inestimable. I had not heard the name of this particular alloy before but there are lots.

[Nick Harbud]

It is somewhat interesting that the hoard has survived in the sea for so long.  I mean, brass is an alloy of copper and zinc, which when exposed to salt water tends to end up as copper due to the zinc being leached out.  Marine brasses tend to add ~1% tin to prevent this, but other metals, including lead are also effective. 

According to the Wikipedia page, these ingots composition is 65–80% copper, 15–25% zinc, 4–7% lead, 0.5–1% nickel with traces of other stuff.

[Ian61]

Dezincification used to be on the A level sylabus, long gone but the experiment to estimate the % composition using conc nitric acid was still around a few years ago when I retired.