The most significant characteristic of the rubies and diamonds is their visual beauty which is what would first attract a buyer to a ring which combines both these gemstones. Their durability as well as their rarity make this a desirable combination. On the one hand there is the depth of color in the ruby and the other there is complete absence of color in the diamond. One plays against the other in a very complimentary way because both depend on the play of light entering the gemstone to realize their full potential.
A fine example would be a catherdral-shaped diamond and ruby cluster set in a basket shaped mount with an 18 carat yellow gold knife-edge shank. Maybe with eleven rubies and eight diamonds.
A center stone of a round brilliant cut ruby which sits proud of the remaining stones. Add eight briiliant cut diamonds surrounding the center and surround them with 10 brilliant cut rubies. Each stone would be supported by four claws, all evenly spaced, coming from the center to the sides, out to a point where they meet the shank.
The ring should be smooth to the touch with no ragged claws and the shank will be smooth and well finished.
As with all jewelry, the ring began life as a design on paper as a sketched detailed drawing by a jewelry designer. The fine detailed drawing would be interpreted by the manufacturing jeweler to produce this piece.
It is likely the mount and setting for such a ring would be made by a process called lost-wax casting. This method is used today to economize on production costs. A wax model of the piece to be produced is made. This is then coated in a thick layer of plaster. Hundreds of items can be cast at one time. This is totally invested in a solid cylinder which is placed in an overn. The wax is melted and becomes liquid adn pours out of a hole in the base thus "losing the wax" and leaving a hollow plaster mold. The correct amount of gold required is calculated and melted down. Centrifugal force ensures it fills all parts of the mold.
Although it is now possible to cast an entire piece of jewelry including gemstones, it is more likely that the gemstones in a quality cluster ring have been set by a traditional craftsman.
The high setting and basket-like mount of a ring allows a lot of light to enter the stones as does the space between each of the stones. You can cleverly give the appearance of each stone sitting entirely on its own while offering a cluster of color, clarity and a very appealing sparkle.
