Cast-in-place, also know as cast-not-set, is a setting technique where the stones are directly embedded into the wax and then cast simultaneously in metal. The result is a jewel where stones and metal literally become one thing, making one-of-a-kind piece each time.
Not all the stones can survive the burnout cycle of casting (which is 12 hours in a kiln at 1200 Degree Celsius), the ones that could be used for this technique are: syntethic stones (like lab created gemstones and cubic zirconia), diamond, ruby and sapphire (someone add garnet to the list, but I haven't tried yet).
Although someone likes to think they have the credit for the technique, as they inveted it (they have not!) the cast-in-place is used since the '90 to set cubic zirconia in cheap, mass produced costume jewellery, because it cuts the time and skills of setters to mount the stones after the piece is made. So it was a technique invented in the jewellery industry to save money and cut the production time.
Now there is another kind of interpretation of the technique: from clean, precise setting to organic, ancient looking, a bit messy jewellery.
Because there is no book or tutorial explaining how to cast stone in place (it was, and still is considered a "trade secret"), the technique simple make me curious to try it on my pieces persuing the perfect-imperfect look.
It's an unpredictable technique where the outcomes could be not exactly what I might expect: sometimes the metal will cover completely the stones, some stones could pop out leaving a hole in the metal, they could break, become cloudy, crack, move inside the fluid metal or change position in the final piece.
My cast-not-set jewellery are the result of countless hours of trials and errors (and errors and more errors), failure and little progress, stones that have literally exploded and uncomplete pieces unable to cast properly.
What intrigues me about this technique is how this process makes the pieces truly unique: I can design a jewel and make the wax model, but then the metal takes over and literally does what it wants.