The luminous on Rolex watches as per the 1965 AEC audit of Rolex USA reveals that Mertz & Bentoli were painting the Tritium on the dial and hands not the dial & hand manufacturers.
What we don't know is from when did M&B start and end applying the luminous material.From a Swiss contaminated building report a M&B building possibly the painting shop/mixing shop operated from 1958 thru to the late 70's, M&B made a decision in 1968 to withdrawn from luminous paint manufacture and specialise in Tritium gases watches for which they are renown for today..so when they ended painting dials and hands for Rolex is not known, most likely some time after 1968.
As part of a supply chain M&B if they received the dial and hands directly from the manufacturers most likely would have had some form of goods inward quality control checking conformance etc. as they would not want to paint dials or hands that may be rejected by Rolex. Conversely,if the dials and hands came directly from Rolex they most likely would paint whatever is sent....so you need to understand the supply chain at the time as to the circumstances and whose QC that would allow non conforming hands eg all red etc to be painted by M&B...I'm sure M&B would not paint something that may be rejected by Rolex.
I know from my now long gone retired watchmaker that he spent a lot of his apprenticeship in the 60's working for a watch manufacturer scraping radium off hands to be replaced with Tritium,for watches in for a service so that creates the possibility of hand repairs and replaced lumi for earlier pieces.
This message has been edited by fatboyharris from IP address 188.8.131.52 on Nov 27, 2017 4:39 AM