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Close enough?

Getting in closer

So-called micro-pavé is often the result of in situ casting techniques in conjunction with CAD/CAM manufacturing. It can be an appraiser's nightmare.
So-called micro-pavé is often the result of in situ casting techniques in conjunction with CAD/CAM manufacturing. It can be an appraiser’s nightmare.

Concerning the name, micro-pavé is typically not pavé. It is a style featuring many tiny full-cut diamonds that most often have been cast in situ. In my experience, it isn’t unusual for a single .50-carat total weight ring to contain 80 or more diamonds, none of which is larger than 1.3 mm (thus the term ‘micro’). Jewellery designers, especially those using computer-aided design (CAD) techniques, are creating jewellery with diamonds mounted virtually everywhere there is a surface larger than 1 mm. The use of computer-aided manufacturing (CAM) allows a wax model to be created with the settings already fully formed and finished. Beads, or more correctly pinpoint prongs, are pre-drilled and precisely placed in the wax model. This has led to the extensive use of the technique of casting the diamonds in situ. For the manufacturer, the result is a significant savings in both money and time. For the appraiser, it’s a nightmare.

Since the diamonds were set into the wax model prior to the casting process, the pinpoint prongs or beads are often bulky and cover a large percentage of the stone. It becomes impossible to properly finish the metal surfaces around and under the stones, so the contrast between metal and diamond is diminished. For the appraiser, the task of accurately measuring large numbers of melee diamonds to within 0.05 mm can be an opportunity to cultivate patience and focus. When we add to the challenge that they are buried in the metal and mounted at odd angles in tiny spaces, it can be a particularly daunting ‘opportunity.’ It isn’t unusual that somewhere around the 80th stone I ask myself, “Is it really important to measure all these diamonds?” We’ll explore that question more deeply a bit later, so for now I’m prepared to offer a definite ‘maybe.’ But how?! I use a table gauge and sometimes a spot of ink from a ‘gel’ pen to mark my place as I systematically work through the item’s various surfaces. It’s a slow, tedious, and inherently imprecise method, but with care and patience, it can still produce credible results. Maybe someone reading this column has figured out a better way; if so, please share it with us before we all go bonkers!

Lest someone think I’m picking on micro-pavé pieces, everything I’m discussing applies to any style of jewellery comprising many small stones intended to amount to a specific total carat weight. True pavé jewellery, as well as ‘line’ or tennis bracelets, riviere necklaces, and cluster settings, all have the same potential to cause problems for appraisers.

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