I have been wondering about the process that was used to produce the two tone effect, some are so intricate and are like works of art. How was this done?

Gary

Gary I think you will find that patterns were made for the desired 2 tone look and then the parts were electro plated. Mercury could have been used but by the time on the American 2 tone watches Mercurys dangers were well known.

Hi Deacon, when you say pattern, do you mean like from gold leaf, or something akin to a stencil, or silk screen process?

Gary

The Watchmakers' Handbook (C. Saunier 1892) describes an electroplating process for gilding, in which a "resist" is applied to a part to cover and protect those areas where you do not want gilding applied. The recommended resist is a mixture of yellow wax, clear resin, fine red sealing wax, and rouge, melted together in a porcelein dish. Though the technique is not explained very well, I infer that this resist mixture would be dipped or brushed onto the part wherever one does not want the gold to adhere. Then, after electroplating, it says to remove the resist with warm turpentine, clean with hot alkaline and finally clean water.

There is also instruction on how to clean and brighten gilt parts to restore original brilliancy: immerse the object in a tumbler of water with 20 drops ammonia, brush with a very soft brush, wash in pure water, then in alcohol, dry with fine linen rag. To restore the "dead surface" of gold objects: place for 2-3 minutes in "chlorine water," rinse in clean water, soap them and finally dry in sawdust.

Cheers.