Behind the scene at the Kingdom A&S Championship: The Viking Hacksilver Bracelet. By Lord Snorri skyti Bjarnarson

In my quest for more authenticity in my jewelry making, I developed a technique, using modern tools, to make stamps to imprint copper-alloy metals with to use to decorate a hammer-forge replica of a hacksilver bracelet from the Cuerdale Hoard. The Vikings made a lot of stamped jewelry; finds of Viking hoards are littered with the stuff, for example, the Spillings hoard in Sweden, dated to the ninth century. There was almost a hundred and fifty POUNDS of silver found there, and at least half of it was either stamped or twisted. Another example is the Silverdale hoard, found near Lancashire in north-west England. A third example from a hoard found in Gotland. image from archaeology.org).

If you look really closely at stuff like this, you can start to discern the shapes of the stamps they used. An extensive inventory of the sizes and shapes of the various stamps used to decorate items in the Cuerdale Hoard can be found in James Graham-Campbell’s book The Cuerdale Hoard on pages 143-148. (Image from Graham-Campbell 2011, 143-148). Once you see the shapes of them, you can begin to make them: triangles with one or three dots in the middle, round dots or ring dots, dotted lines, straight bars, and others.

For practical instructions, visit Snorri’s House at https://snorri.blog/2019/04/27/viking-stamped-jewelry/#more-610

Then, I decided to cast a silver ingot and hammer-forge it into a replica of a hacksilver bracelet from the Cuerdale Hoard, using the stamps I made for the decorations. I first did some research on what exactly I would be creating. I acquired the book The Cuerdale Hoard by James Graham-Campbell. This book details not only the items of the Cuerdale hoard, but the many other Viking-Age finds from Britain and Ireland in the British Museum. It also contains an inventory of the various shapes of the stamps used to decorate many of the finds. I chose to try and recreate a fragment of a hacksilver bracelet found on page 317. (Image from Graham-Campbell 2011, 317)

The first step was to carve a depression into the soapstone to hold the silver shot and scrap. The mixture of pure silver casting grain (.999 silver) and sterling silver scrap (.925 silver) results in a very authentic alloy. The silver found in the Cuerdale hoard was particularly pure for a Viking-age find; all of it is above 90% silver, and most is above 95% silver (Graham-Campbell, pp.82). By mixing pure silver with sterling silver, in a 2:1 ratio, I have made an ingot of approximately 97.43% purity. Using soft stone molds, as well as clay and sand molds, is a period method for casting ingots (Pedersen, pp.90, “Soapstone moulds have also been found in the other Viking-period towns of Scandinavia, and in York”). I tried chiseling the depression into the stone with an old flathead screwdriver and a mallet, but it was slow going, so I turned to modern power tools. The depression was enlarged with a Dremel rotary tool and a sanding drum, then even larger with a sanding drum in a handheld drill. At the end, I wiped down the stone with mineral spirits to remove any remaining dust.

I placed the silver into the depression and began heating it. I heated one side until melted, flipped the proto-ingot over, and heated that side until melted. I repeated this process many times, until the ingot looked mostly homogenous. The ingot was then cooled in the metal bowl filled with water and brought to the anvil.

I used the unpolished side of the 2-pound hammer to begin flattening the ingot into a rectangular shape. After every few hits, the silver needed to be annealed, which involved heating it with the torch until it was the color of an orange creamsicle, then quenching it in the water. Silver work-hardens very quickly, which necessitates the constant annealing. Once the ingot had four flattened sides, I clamped the 2-pound hammer in my vise, with the shaped and polished side upwards. I used this as an anvil and used the shaped and polished 16-ounce hammer to begin drawing the ingot out into a long flat billet. The rounded hammers, together with a glancing striking technique, effectively squeeze the silver like a roller, stretching and flattening it. The ingot was drawn out until it was about six inches long, one and a half inches wide, and three thirty-seconds inches thick in the center, down to about one sixteenth inch thick at the ends.

At this point, the billet was very irregularly shaped, and the surface was very rough from the hammer blows. I laid it on my anvil and used a small jeweler’s planishing hammer to methodically smooth out the surface. Planishing is a method of finishing metals, the process of using a hammer with a slightly rounded and highly polished face to lightly tap out dents and imperfections in the surface of metal. While the metal never gets truly smooth from planishing, with good technique you can trade large hammer marks for much smaller hammer marks. This takes many passes, planishing the entire surface of the piece. I did three planishing passes on this billet annealing the piece between each one. As the surface was going to be marked with decorative stamping, I felt this sufficient.

Once the billet had been planished, and annealed a final time, I used a ruler and pencil to find the maximum dimensions I could get from it, while staying true to the shape of the extant piece. I ended up marking off a piece six inches long by one and a quarter inches wide at the center, tapering down to three-quarters of an inch wide at the ends. I used my Beverly shear to trim the piece to these dimensions. I used a belt sander and files to round off the edges and polished the entire thing on my buffer.

Picture right are the materials and tools used to produce the hacksilver bracelet. The hammer surfaces are reshaped to get the desired effect, and the set of stamps are hand made to get the correct period patterns. Next, it needed decoration. The period example has imprints from two different stamps: a dashed line, and a shape resembling a heater shield with three dots in the shape of a triangle inside it. Not having stamps that made these exact shapes in the exact sizes necessary in my collection, I set out to make them. I cut two sections of stainless-steel rod, shaped their ends using a belt sander and files, used a center punch tool to make the three dots, polished them with the buffer, and heat treated them by heating their ends red-hot and quenching them in water. Without heat treating, the ends would quickly deform when hit with a hammer. After heat treating, they are quite hard and durable.

I again used my pencil and ruler to mark the center line of the silver, laid it flat on my anvil, and stamped the length of this line with my new dashed line stamp and an eight-ounce ball-peen hammer. Then I used the shield stamp to make a line of imprints with their flat sides against the dashed line and filled the spaces between their points with the same stamp reversed. I did this on both sides of the piece. Finally, I used a mallet and a round piece of oak dowel clamped in my vise to beat the piece into a bracelet shape. The finished Cuerdale Hoard hacksilver bracelet (pictured right)

Future Improvements:

While casting the ingot in soapstone is a period method, it was likely done historically with liquefied silver. My method of heating the silver with a torch in the mold did not get quite hot enough to completely liquefy the metal, causing my piece to not be completely homogenous. This resulted in some cracking and separation during work, and especially when it was bent. Some of this may have been mitigated if I had annealed the silver once more after I finished stamping it, however this would necessitate polishing the silver another time, and polishing a stamped piece is difficult, but could have been accomplished by use of a pickling solution. In period, they would likely have melted the silver in a crucible of some sort inside a forge or furnace and poured it into the mold. Another option would be to cut my mold into a firebrick instead of soapstone; modern firebrick reflects a lot more heat than soapstone, which absorbs more than it reflects, and the silver will get much more liquid.

If I cast a longer ingot, I would not need to spend as much time drawing the metal out. Carving the stone takes a lot less time than hammering and annealing the metal fifty times.

Better hammering technique would result in being able to form a billet that needed less, or no, trimming. With practice I will be able to hammer things directly into the shape I have chosen.

Bibliography:

British Museum Collection Online: The Cuerdale Hoard (737 items)

https://research.britishmuseum.org/research/collection_online/search.aspx?place=29472&plaA=29472-3-1

https://research.britishmuseum.org/research/collection_online/search.aspx?place=29472&plaA=29472-3-1 Graham-Campbell, James, and Karen Hughes. The Cuerdale Hoard: and Related Viking-Age Silver and Gold from Britain and Ireland in the British Museum. British Museum Press, 2011.

Pedersen, Unn. Into the Melting Pot: Non-Ferrous Metalworkers in Viking-Period Kaupang. Aarhus University Press, 2016.

Image Gotland hoard:

https://www.archaeology.org/issues/240-1701/features/5123-sweden-gotland-viking-wealth#art_page3

Image Cuerdale hoard:

https://research.britishmuseum.org/research/collection_online/collection_object_details/collection_image_gallery.aspx?assetId=276437001&objectId=65922&partId=1