Well, we seem to have 2 threads discussing this "Silver Steel" term. Here is a quote from Smallbore per his book, I moved the section on Silver Steel up:
Gun Notes
Damascus Terminology
Prior to the development (in the 1880s) of the technology to produce steel barrel tubes in one piece, barrels had been made by a process of hammer welding different grades of iron and steel around a mandrel. The resulting, figured, barrels are generally referred to as ‘Damascus’ by modern writers. However, ‘Damascus’ barrels were made in a wide variety of grades and the manufacturing process varied accordingly. Here are some common terms encountered when reading contemporary writers, about types of Damascus barrel and what they refer to:
English Steel Damascus
This was composed of steel and iron in six-parts-to-four proportions. Tubes made with higher steel content, usually eight-parts to two-and-a-half of iron were termed ‘Silver Steel Damascus’. In either case, the best barrels used three or more twisted rods of metal and were well figured and tough.
Laminated Steel
This was made from best quality steel scrap mixed with some charcoal iron and worked under a forge hammer repeatedly until the close and even grain desired was achieved. The metal was then rolled out and shaped into a tube in the conventional manner. Greener praised the practical, hardwearing qualities of laminated steel. Unfortunately, from an aesthetic viewpoint, it lacked the intricate pattern of other forms of Damascus barrel.
Stub Damascus
This was usually made by heating old files, quenching the red-hot metal to make it brittle and then pounding it into very small pieces. This was added to a quantity of nail stubs from horse-shoe nails. The mixture was heated in a furnace to fuse the component parts. The metal was then hammered into rods and twisted and welded into tubes in the usual manner.
Skelp
This was a cheap variety of barrel material also referred to as ‘Twopenny’ or ‘Wednesbury Skelp’. The iron used was of lower quality scrap but if well forged and hammered could be serviceable. Skelp tubes were not used for good quality guns.
Sham Dam
A poor quality steel barrel was formed by welding along the length and then wrapping a thin Damascus layer over the top to deceive the buyer (or gunmaker) into believing the barrel to be a higher quality one of Damascus construction.
Pointille Twist
This type of Belgian tube was very well figured and free from ‘greys’ and became popular with some British gun makers in the1880s. It looked attractive but lacked the toughness of British Laminated Steel.
Remember he is talking only about English terminology.
Regarding "Silver Steel". There is a physical limit for the steel content and a set of barrels to be able to show a pattern. He seems to be suggesting that silver steel is about 70%-75% steel. In the Belgian literature the figure of 60% steel is often quoted. I do not know of any source that shows the differences between the various steel levels and it's impact on the displayed pattern.
I have seen examples of specific patterns that seem closer to 50/50. Here is an example.
A clear picture of a "Silver Steel" barrel would be helpful at this point.
Pete