Following an order similar in character to that used in clay designing, problems in both base and precious metals may be divided into four classified groups as follows: flat, square, rectangular, or irregular planes; shallow circular forms; low cylindrical forms; high cylindrical forms. Designs included in the first group, flat planes, comprise such problems as are typically represented by tie pins, fobs, rings, and pendants. The design problems presented by these examples are so important that it is wise to restrict this chapter to flat planes.
Rule 10g. The inceptive axis should pass through and coincide with one axis of a stone, and at the same time be sympathetically related to the structure.
Rule 10h. The position of the inceptive axis should be determined by: (1) use of the project as ring, pendant, or bar pin, (2) character of the primary mass as either vertical or horizontal in proportion.
Inceptive Axes and Points of Concentration
The semi-precious or precious stone is commonly found to be the point of concentration of these designs. The inceptive axes of tie pins, pendants, and fobs are generally vertical center lines because of the vertical positions of the objects when worn. The inceptive axes, moreover, should pass through the point of concentration and, at the same time, be sympathetically related to the structure. Rings and bar pins are frequently designed with horizontal inceptive axes, so determined by their horizontal characteristics and positions.
The point of concentration for tie pins, pendants, and fobs in formal balance, in addition to coinciding with the inceptive axis, is generally located above or below the geometric center of the primary mass. The point of concentration for rings and bar pins is placed in the horizontal inceptive axis and centrally located from left to right.
Typical Processes of Enrichment
Economy of Material
As a step preliminary to designing, and in order that the enrichment may be conventionalized or adapted to conform to the requirements of tools, processes, and materials, it is now imperative to become familiar with a number of common forms of surface enrichment in metal. There are eight processes frequently encountered in the decoration of silver and gold: piercing, etching, chasing or repousséing, enameling, inlaying, stone setting, building, carving. To these may be added planishing, frosting or matting, and oxidizing as methods employed to enrich the entire surface. Economy of material is of prime importance in the designing of precious metal and, particularly in gold projects, conservation of the metals should be an urgent consideration in all designs.
Rule 10a. Designs in precious metals should call for the minimum amount of metal necessary to express the idea of the designer for two reasons: (1) good taste; (2) economy of material.
Evolution and Technical Rendering of Processes