Sometimes we find a stone that has a non standard size or shape. This rose quartz is a good example. It is a high dome cabochon that has lovely color and is 19x22 mm in size. A standard calibrated mounting is not available in this size. So we will make one to fit. Because the base should be fairly thick and sterling is expensive in 20 gauge I chose single clad silver filled sheet
http://www.riogrande.com/Product/3-1-10-Silver-Filled-Single-Clad-Sheet-20-Ga/105379?pos=3. This is bronze with a layer of sterling 10% by weight on one side of the sheet. In the picture you can see the bronze side. I also used gallery wire 4mm wide and a double half round sterling wire for the shank.
First step is to cut a piece of gallery wire close to the circumference of the stone making sure it will be able to overlap by 1/4 inch. Form it roughly to the cabochon by wrapping and pressing it to the stone.
Next using a sharpie fine point marker and holding the wire wrapped around the stone mark the length on both ends at once.
Next cut through this mark and file flat the ends so they will meet up evenly with no gap.
It should look like this. The pattern wont always match but don't try to make it match because it wont fit the stone if you do.
Here it is sitting on a ceramic soldering taper. I soldered the bezel with hard solder. You will want to have 3-4 grades of solder to do a project like this at first because the hard melts at a higher temperature than the medium which is used to solder the bezel to the plate..and use soft or easy for the shank attachment. This keeps previous joins from coming apart.
next insert the stone and form the bezel to fit exactly by pushing on the base of the bezel all around.
Next trace the shape loosely onto the backing sheet and cut it out. I use a jewelers saw for this...shears will distort the metal and you want this to be perfectly flat to solder on the bezel.
Set the stone and bezel on the cutout sheet to confirm it fits The remove the stone and pickle both pieces to clean and prepare them for soldering. I place the pieces on a wire grid on top of a soldering tripod..you can use a charcoal block or ceramic soldering block as well. Place chips of solder around the inside edge of the bezel wire and apply flux to the whole thing. Then heat the base with a soft flame and when the flux melts begin to move the point of the flame around the inside heating the area to be joined until the solder flows.
You can see the solder flowed well and has round all around the edge attaching the bezel to the plate. Put this in the pickle pot and when it is clean the silver will be white and ready for the next step.
I chose this traditional double wire and bent it around the ring mandrel after sawing through the center to form the Y shape which will be supporting the large stone.
I next filed the edge of the base to the edge of the bezel and smoothed it with an emery board.
Here the shank wire is prepared and the points of attachment filed flat. At this point it is good to file the ends smooth and remove sharp edges.
Place it on the base and using easy solder attach the shank, then pickle again and begin the finishing process. File first, any rough edges then using emery boards or sandpaper in 400 grit wrapped around a stick smooth the file marks away. Then using your favorite rotary tool like a heatless mizzy wheel polish all surfaces.
I finished with a wire brush and some bobbing compound on a rotary buff.
The inside should be finished with clear or milky stones because the surface will show through the stone. Here I used a rotary nylon brush and tripoli to give a smooth finish.
The all that is left is to mount the stone. If you are successful in making the bezel the right size the stone should sit with no wiggle in the bottom of the plate. If you are using an opaque stone glue can be used.. In my case I used the tall prong tops to hold the stone by pushing them against the stone all around. I always start at 1-3-6-9 around the clock then when the stone is locked in do the rest of the prongs until the stone doesn't rattle.
And there we have the final result a custom made ring.
Part of making jewelry is buying the components at a good price. I have discovered a good source for acquiring lots of parts is Ebay. More stuff than you will ever need. Everything in this shot is from sellers there. The first three rings on the left are from Hong Kong....sterling with fake stones.I paid .99 for each with $4 shipping for the 3.I will pull the cheap stones and under neath is a good shank that can be used..even the mounting can be modified to work in a custom made piece. Going around the top row in this picture we have some sterling mountings from jamminggems on ebay $11-18 each and they are prepared with proper easy to mount prongs already notched. The stones are real, quartz, peridot, and citrine. They come from Thailand and cost on average $5 The cutting is perfect..buying smart I get these at the price of glass and they drop right into the pre-notched mounts. The bottom pieces are today's project. 
A rectangular druzy and a bit of gallery wire already bent around the stone and a sterling band are ready to become a ring. But first we need to measure and transfer the size to the sheet metal for the base. Instead of measuring and marking or tracing around like I showed last time I wanted to show you the right way. Using a pair of dividers from the hardware store we can accurately measure and mark all at once and do it perfectly.
Dividers are like a compass with two points. These are machinists dividers. Place them across the length careful to leave a tiny gap between the wire bezel and the point.
Place the dividers on the metal and pull across with one point over the edge of the metal.
This leaves a perfectly parallel scratch the length of the bezel.
Do the same with the width.
Now we have a squared up rectangle ready to be cut out.
Put the stone into the bezel and place it onto the sheet. If it matches(and it will) cut out the piece of sheet stock with your jewelers saw.
Some folks will try to tell you the saw is slow, but its very accurate if used correctly. We have made the base plate for the ring sized correctly with very little to file off and never used a ruler. Simple and accurate. The divider is your friend.And they are inexpensive. Here is a link to some that are similar to the ones I used here and they sell for less than $6 http://www.jewelrytools.com/eurotool/jewelry-dividers/Divider-3-Inches.html
This is the finished ring.Next time we will explore those HK mounts and make another drusy mount to fit.
