An unusually silvery Constantine VII follis

[Finn235]

Got this one in a recent lot and thought I had a silver coin until I realized that it's Sear 1761, an "AE" follis of Constantine VII

Byzantine is way outside of my wheelhouse - any insights into why this might be colored like this? Alloy cut with lead perhaps?

[ela126]

Interesting patina for sure, very uniform

Looks like the core might be standard bronze/copper, you can see on the reverse the coppery parts peeking out.

I know Alexandrian minted coins have high contents of lead in them. Circa early 7th century. Being this is earlier 9th century from constantinople, i doubt it.

Seems to have been well cleaned at some point, the detains are quiet bold and unmasked by dirt. My journeyman guess would be some type of repatination effort after cleaning, could not say how recently though.

[Finn235]

Or I wonder if somebody tried to silver plate it at some point? 

[Ancient Coin Hunter]

That's weird. I am thinking it might be a lead cast? In which case it would be a modern fake. Anyway, it would be interesting to do a metallurgical analysis on it. What is the weight?

[Finn235]

On 10/18/2023 at 12:21 PM, Ancient Coin Hunter said:

That's weird. I am thinking it might be a lead cast? In which case it would be a modern fake. Anyway, it would be interesting to do a metallurgical analysis on it. What is the weight?

4.17g on my scale. No sign of casting on the seam, plus the coin is double struck on the obverse. What do these typically weigh?

[sand]

It may just be a light gray patina, on a bronze coin.

[Ancient Coin Hunter]

2 hours ago, Finn235 said:

4.17g on my scale. No sign of casting on the seam, plus the coin is double struck on the obverse. What do these typically weigh?

Weight seems OK, probably not a fake at this point. But certainly unusual metallurgical circumstances, to be sure.

[Tejas]

Is it possible, that certain chemical reactions have given the copper a silver-grey surface?

I have the coin below, which should be copper, but seems to be good silver. 

I also have this coin below, which has been silvered at some point. The silvering is quite thick and shiny, but copper shows through at the rim:

 

 

 

 

Edited October 20, 2023 by Tejas

[theotokevoithi]

Nice coin.

It is cleaned and patinated (moderate for a better colour than copper colour).

S,Cl and heatιng.

It can happen to the ground, but this is not the case.