As usual we must conclude the illustration of this particular branch of the trade with a warning, for if Baron Rothschild had to regret the acquisition of expensive enamels, and he is not the only conspicuous connoisseur to do so, what is the fate likely to overtake the first exploits of a neophyte in the field! If not assisted by a first-rate expert, the freshman had better not meddle with enamels for a long time, but assuage his passion by going and admiring well-known and authentic pieces in famous museums. CHAPTER XXII METAL FAKES Metal work--The bronze family: brass, copper, and their various colours and patinæ--Beaten iron work--Arms and armour-- Artificial rust and chemical oxidation--When the imitators of arms and armour used steel and when iron--Cast iron pieces-- Chemical tests--Difficulties in the connoisseurship of arms and the story of three shields--Old and modern imitations-- Silver work--Its colour and oxidization--Why artistic pieces in precious metal are in danger of being destroyed--Fashion one of the dangers of silver plate--How far reliance may be placed in marks--Gold work--The tiara of Saitafernes--Jewels and their extreme rarity--Imitations and forgeries of all ages-- Advice to the non-initiated in the art of buying jewels. When speaking in another part of this work about the methods of conferring an appearance of age to newly cast bronze, we remarked that the faker’s best accomplice in the ageing process was chemistry. The colouring and bronzing of metals in fact is usually accomplished by one of two methods, by the action of chemicals or by the application of bronze powders rendered impalpable and used as a pigment. The latter method is mostly used in modern industrial art, but has, nevertheless, been applied in imitating antiques and in disguising mended parts, etc. It is often used with success in the case of imitations of excavated objects which generally have a bluish-green patina. This may be imitated to deceive the eye of the beginner only, by the application of green-bronze lacquer of a dull lustre, or of green varnish. The green of the bronze colour is best prepared by mixing Frankfort black with chrome yellow. These are, however, but cheap and not always convincing expedients, the real way to give tone and colour to bronze and other metals is by resort to chemistry.