Gold Bar Hallmark Q.

by Jeffrey Learned
(Seattle WA.)

I've been following gold for some time and have made a number of "smaller" purchases (less that 2 kilo's total) of gold coins and bars. I am most interested in bars and came across one with the hallmark "J & M Co Assay 2 Oz." The bar is approximately 4mm x 2mm x 5cm deep. It looks older and has smoother edges, like a 100 gr pamp. In my research I cannot find any bars on line that look like it. I thought the "J&M Co." possibly stood for "Johnson Matthey." Any ideas out there?