Hand Chasing on silver or metal is the  technique of detailing the front surface of a  sterling or other metal article with various hammer-struck punches. Your pattern will be flat or indented into the metal..

Coin Silver: Sterling is 925/1000 parts pure silver and never changes. Coin is more variable; the purity of metal matching, that of contemporary currency. When there was a short supply of silver, before the discovery of the huge silver mines in the American west,  coins were literally used as metal stock, especially in the colonial era. Because of the multiplicity of coinage in use, it has varied from 835/1000 to 925/1000. It was never an enforceable standard like sterling, but was a means for silversmiths, lacking a national standard of assay, to assure clients of the quality of their silver. By the 1820s, with flat-rolled silver stock readily available, it became an arbitrary benchmark set at 900/1000 and remained so until the British sterling standard was adopted by Gorham, Tiffany, and others in the 1850s.

Electroplating: The process of putting a metallic coating on a metal or other conducting surface by using an electric current. It is used to improve the appearance of materials, for protection against corrosion, and to make plates for printing.

The thickness of the layer deposited on the article depends on the strength of the electric current, the concentration of metallic ions, and the length of time the article has been in the solution. The terms triple-plated and quadruple-plated indicate various thicknesses of plating, not separate layers deposited on the surface.

Resource: Melvin Bernstein, "Electroplating," Discovery Channel School, original content provided by World Book

Engraving on Metal is the process of cutting shallow lines into silver or another metal with a sharp graver, reproducing artwork which has been drawn on a metal article.  Hand engraving removes metal when cutting, Machine engraving does not remove metal,. Bright cutting is another form of engraving which when viewed is very reflective because of its flat, angled cut.

Repoussé on metal is the process used to emboss a sterling or other metal object from the back or inside with larger punches. The pattern will push out from the front.