Looks like appliance enamel to me!
1921 Gibson A-3
© Frank Ford, 1999; Photos by FF
Here's a classic bit of Gibson design - the colored finish. Brother, you wouldn't miss this mandolin from the back row of the balcony!
After years of producing black face and sunburst finish instruments, Gibson introduced a striking new one. It was described in the catalog as having an ivory colored French enamel finish. Only the A-3 mandolin was produced in this color, and I suspect it was far from a best seller.
As you look it over, notice that the fingerrest and its fittings are made of matching ivoroid, as is the binding.
Please click the small image