Pointillé is a decorative technique in which patterns are formed on a surface by a means of punched dots. The technique is similar to embossing

Repoussé and chasing

Repoussé or repoussage is a metalworking technique in which a malleable metal is ornamented or shaped by hammering from the reverse side to create a design in low relief. There are few techniques that offer such diversity of expression while still being relatively economical...

 or engraving

Engraving

Engraving is the practice of incising a design on to a hard, usually flat surface, by cutting grooves into it. The result may be a decorated object in itself, as when silver, gold, steel, or glass are engraved, or may provide an intaglio printing plate, of copper or another metal, for printing...

 but is done manually and does not cut into the surface being decorated. Pointillé was commonly used to decorate arms and armor starting in the fifteenth century http://www.metmuseum.org/toah/hd/dect/hd_dect.htm. The Holy Thorn Reliquary

Holy Thorn Reliquary

The Holy Thorn Reliquary was probably created in the 1390s in Paris for John, Duke of Berry, to house a relic of the Crown of Thorns. The reliquary was bequeathed to the British Museum in 1898 by Ferdinand de Rothschild as part of the Waddesdon Bequest...

 in the British Museum

British Museum

The British Museum is a museum of human history and culture in London. Its collections, which number more than seven million objects, are amongst the largest and most comprehensive in the world and originate from all continents, illustrating and documenting the story of human culture from its...

, made in France at the end of the 14th century, has very fine and delicate pointillé work in gold.

Common uses of pointillé

Pointelle is commonly used:

• in the decoration of metallic arms and armor
• in the decoration of hand-finished firearms
• in bookbinding
  Bookbinding
  Bookbinding is the process of physically assembling a book from a number of folded or unfolded sheets of paper or other material. It usually involves attaching covers to the resulting text-block.-Origins of the book:...
  
  to finish hand-made bookcovers http://palimpsest.stanford.edu/don/dt/dt2621.html