SHOW: Rings 88

Title:      Ring.
General:    18K Gold Ring, set with Diamonds. This ring was made for a lady
            with severe arthritis. The ring hinges open, and has a catch
            between two of the Diamonds.
Material:   18K Gold.
Gem:        Diamond.
Method:     Constructed.
Finish:     Polished.
Mechanics:  Bezel set. The Hinge is a three leaf type, the catch is a over
            the hump click type.
Designer:   W.van Heeckeren.
Craftsman:  W.van Heeckeren.

Price:      AUS $ 12500.00.


        18K GOLD is a ternary Gold alloy consisting of:
                        750 parts/1000 Pure Gold.
                        125 parts/1000 Pure Silver.
                        125 parts/1000 Pure Copper.
 Annealing temperature: 750 degrees Celsius.
   Melting Temperature: 950 degrees Celsius.



        Bezel Setting is done by making a sheet metal surround (the
                bezel) for the stone.  Once the jewelry has been finished
                the stone is then set.  In setting the stone, the stone is
                placed in the bezel, and the bezel is shrunk in around the
                stone, by pushing it in little by little evenly around the
                circumference, until the metal seals tight against the
                stone. As a finishing touch a flat graver is used to bright
                cut the edge of the bezel at right angles to the plane of
                the bezel.


Technical Data for DIAMOND.

name:                          DIAMOND
colour:                        Colorless, yellow, brown, sometimes green, blue, reddish, black
colour of streak:              None possible
mohs hardness:                 10
specific gravity:              3.47 - 3.55
cleavage:                      Perfect
fracture:                      Conchoidal to splintery.
crystal system:                Isometeric ( cubic ); mainly octahedrons, also
                               rhombic dodecahedrons, cubes, twins, plates.
chemical composition:          C, crystalised carbon.
transparency:                  Transparent.
refractive index:              2.417 - 2.419
double refraction:             None, often anomalous.
dispersion:                    0.044
pleochroism:                   None.
absorption spectrum:           Colorless to yellow: 4780, 4650, 4510, 4350, 4015,
                               4230, 4155, 3900 Blue-green: ( 5370 ), 5040, ( 4980 )
fluorescence:                  Variable; Colorless and yellow: mostly blue. Brown
                               and green:  often green.