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History of Granulation

The textural, dotted patterns you see on my work are created through an ancient technique known as granulation. It’s a style many jewelry lovers are familiar with visually, while being unaware of the details that go into its manufacture. So, what is granulation?

Put simply, it is a surface decoration technique in which tiny spheres (granules) of metal are arranged in patterns across the surface of a piece of jewelry, and then fused on with the heat of a torch. The technique is truly ancient- there are some examples of it in Egyptian jewelry of 4,000 years ago, and Sumerian pieces from 1,000 years before that, but it was mastered by the Etruscans of 700 BCE, living in what is now Tuscany.

The Etruscans remain something of a mystery to modern scholars, as the sheer perfection of their work seems to come from a civilization far more advanced than theirs seems to have been. Created in high-karat gold, these pieces amaze and delight with their intricacy and glorious levels of detail. If you want to be lost in amazement at the skill of these craftspeople from so long ago, check out this book. The symmetry, fineness of technique, and perfection of the work are seen not only in photographs, but in microscope scans of the works. I’m inspired every time I see what they achieved, it’s stunning to think about.

Granulation had another heyday in the mid to late-1800’s, as excavations of ancient cities all over the world were undertaken, and the original treasures toured Europe and inspired new interpretations. The house of Castellani, whose members had close ties to prominent archaeologists of the day, were at the forefront of what we now call the Archaeological Revival style. The three main members of the house- Fortunato, the father and Alessandro and Augusto, his sons, worked together to research and revive this technique, which was no small undertaking.

The techniques that created the ancient Etruscan pieces were not recorded in any lasting way, and the details of the process could not be learned just by looking at the pieces. In particular, the way the granules were attached to the background was puzzling, since no evidence of solder was seen, meaning that the way a 19th century jeweler would do the work was not the way the Etruscans would have.

Yes, please!

Alessandro in particular was fascinated by this puzzle, and perhaps because he had lost an arm in an accident and couldn’t create jewelry, he applied himself to researching it. Traveling throughout Europe, he collected Etruscan works to study and to preserve as Italian heritage pieces, protecting them from leaving the country that inspired them.

Once back at their studio, replicas were made and sold to the many people who could afford the newly-trendy style. Three stunning examples of their work are seen here, which I photographed at the lovely Walters Art Museum in Baltimore- worth a visit, even though they wouldn’t let me take these necklaces home.

There is some debate about whether the Castellanis fully revived the ancient technique as the Etruscans did it. Their writings claimed that they did, but examination of Castellani pieces shows that in some, at least, more conventional soldering techniques were used, although more artfully than by many other jewelers.

Later scientists built on the studies of Castellani and others, and in 1934, Henry Littledale filed a patent for what scholars now believe was the main technique used by the Etruscans, called eutectic soldering. In this technique, a solution of copper salts is painted over the surface to be decorated before the granules are placed. The copper lowers the melting point of the gold wherever it is coated, and so the point of contact between the spheres and background comes together while the whole piece is still below its overall melting point.

This seems like an insignificant difference- so what if the piece is soldered or created without solder? Whatever works, right? But once you look at a few pieces made with either technique, the differences are clear.

Really- clarity is the difference, at least to me. Truly granulated pieces have a clarity and crispness to the design, and since the granules are attached just enough to keep from falling off, there is a levity to them, with the best examples seeming to show patterns that float above the background. Think about dropping a scoop of ice cream on a cold sidewalk vs. a hot one- the point of contact will reflect the greater heat, and the floating roundness will sag into the background. Solder is like the melted ice cream in our silly example- it muddies the design and dulls the crispness of the pattern.

Besides technical skill and mastery of the chemistry involved, the other important factor in true granulation is the purity of the metal. Gold of 18k or higher can be granulated, as can fine, unalloyed silver. As less wealthy people started to demand their own luxuries, lower karat alloys were created and used to make jewelry affordable for the masses. Granulation is not possible with less pure metal, and so it fell out of style again.

Recently, granulation has had something of a Renaissance, partly fueled by the worth of gold as an investment (may as well make that nest egg into something beautiful you can wear until the economy collapses!), and by new alloy technology. This is where my work comes in, since the creation of the Silver alloy called Argentium makes granulation possible in a whole new way. Watch for a post about that development soon!