These rosettes

In the USSR, for a while it was "fashionable" on the gear lever knob set of transparent material cast into rosettes. General manufacturing techniques such handles this - Several pieces of Plexiglas (about 5 x 5 cm. Drilled in the center of the drill 6 millimeters and screwing them on long bolt glue dichloroethane well styanuv them among themselves to bubbles left. In a piece of thick plexiglass than something like bormashinki milled something like roses and petals painted lacquer tsapon zatonirovanym paste of colored pens. The lower part of the future pen on a lathe and then rounded to one end dihloreetanom paste rosette (rosettes inside) and clamped all this stuff for a couple of days in a vise until complete dihloretona drying. Then the resulting product is again clamped to the lathe and adjusted to the desired shape of the handle with threading. The last operation - vyshkurivanie fine sandpaper traces cutter from turning and polishing on a felt circle with GOI paste for a perfect transparent surface. Variations technology but the basic principle I described.
If you get plexiglass and lathe plus felt polishing wheels and get dichloroethane, bormashinku with different nozzles, vise and drill sets more and taps - make this easy to handle and themselves.