The posts that are read the most on this blog are those discussing dating antique jewellery so I thought I would add a few more on this very broad topic. It is not easy to date jewellery if it is not hallmarked and as it wasn’t compulsory to hallmark jewellery in many countries for various periods, not all that much jewellery is hallmarked. There are, however, some other ways to date jewellery. For instance, clasps, which I have talked about before, can tell a lot about the age of the piece.  However, what I want to talk about today is the way gemstones are set. The technology (or lack thereof) available to the jeweller at any given time in history was a key factor in deciding how gems would be set. Also important was the effect that was being sought, for instance, should the gem sparkle in candlelight, did the colour of the stone need to be deepened, and so on.

Up until the 16th century, there were really two main settings for gemstones – the box setting and the collet. The box setting is just that, the jeweller made a small lidless box and placed the stone inside it, then the sides of the box were hammered in to hold the stone. The shape of the box was usually formed to fit the shape of the stone. There were different versions of boxes, one being the tart-mould or pie crust box seen in the 12th century.

The collet setting is similar but it might consist of just a collar without a base. The top of that collar is pressed around the stone to keep it firm, called rubbed-over setting. Later, the sides were pressed into vertical ridges.  Sometimes, with more fragile stones, the collar was cut into tiny ribs or serrated peaks, like claws, and the top of each serration or claw was then gently folded over the stone. There are examples from the 12th through to the 15th centuries of the side of the box or collet being pulled down to create prongs. The sides of the setting could be cut down to allow more of the stone to be seen.  The collet setting is also known as the bezel setting.

Originally, the box setting was used because of the way gemstones were cut. Generally, stones were either cabochons, rounded polished stones, or they were pyramid shaped or flat topped.  Diamonds in particular were used in their original octahedral form up until about the 14th century. There were no facets and no attempts to allow light to reflect through a stone. This meant that the box setting was appropriate as it held the stone secure, which was all that was needed.

Even in the Renaissance, much of the focus of a piece of jewellery was on enamelling the gold surrounds of the gem and on ring shoulders, with the stones there just to provide a bit of colour.

Gem cutting techniques began to improve in the 12th and 13th centuries, resulting in facets in stones. The diamond point cut was introduced around 1330, the table cut around 1450 and the rose cut began to appear around the 1500s. However, closed settings continued to be used to allow for foiling of the back of stones to enhance their colour and clarity.

Closed back Georgian ring

Closed back gems continued for the whole of the 18th century, particularly for dark and opaque stones and paste, but more open settings began to be introduced, still using either the rubbed-over collet setting or the rib or peak collet setting (Bury, 50, 138). Armstrong commented that: ‘For the first 50 or so years of the eighteenth century, [diamonds] were still mostly rose-cut, backed, foiled, and tightly held in claw setting. Then, slowly and cautiously, jewellery began to open out. Brilliant-cut diamonds were introduced, in claw or coronet settings, with the jewel lifted up and held above the base’ (Armstrong, 150). By the end of the period, backings were left off.

Partially open backed collet setting

References:

Nancy Armstrong, ‘Jewellery: an historical survey of British styles and jewels’, 1973, Lutterworth Press

Duncan James, ‘Antique Jewellery: Its manufacture, materials and design’, 1998, Shire Publications

Jack Ogden, ‘Diamonds: An Early History of the King of Gems’, 2008, Yale University Press.

Shirley Bury, ‘Jewellery: 1789-1910, vol 1’, 1991, Antique Collector’s Club