"Or sitting in the archives of the Museums of Birmingham, Wednesbury, Shrewsbury?"

Exactly Peter. W. Greener claimed to have invented Laminated Steel, but I've found no patent, nor did he name his invention. With his penchant for self-promotion (ie. Greener cross-bolt & Greener side safety) one would think 'Greener Laminated Steel' would be found stamped on his guns.
Might have to make the trip, but do they speak American in Wednesbury?