Standard Gold and Silver Trial Plates. 85 



the purity of the ingredients are perfectly certain, still it is 

 possible that in their combination errors may creep in. If, for 

 example, the mass be kept too long in a state of fusion an 

 oxydation of a portion of the alloy will take place, and thus 

 render the casting too fine ; if there be not sufficient heat in 

 the furnace, or if the melted mass be not duly stirred so as to 

 effect a proper chemical action and consequent union of the two 

 metals, the plate will assuredly vary in purity in different parts. 

 There are other practical points to be attended to in the 

 creation of new trial -plates, but, of course, in the hands of the 

 Goldsmiths' Company they are not at all likely to be over- 

 looked. It is not often, indeed, that trial-plates have to be 

 renewed. A small portion only of each, whether of gold or of 

 silver, is consumed at each Pyx inquiry, and they last therefore 

 for many years. In 1660, a gold trial-plate was made by the 

 Goldsmiths' Company, this was followed by another in 1668, 

 the next was cast in 1707, a fourth was produced in 1728, and 

 that which is used at present came into existence in 1829. 

 Silver plates were made on the same occasions, and it does not 

 appear that at any time a new gold plate was made without a 

 corresponding plate of silver being also prepared, and vice versa". 

 The gold trial-plate now in use as a check upon the British 

 Mint may justly be pronounced of the true standard. It has 

 been certified to be so, indeed, not only by the Goldsmiths' 

 Company, but by the authorities of the Mints of Paris and 

 of Amsterdam, to whom small pieces of it were sent for exami- 

 nation. The same remark will apply to the silver trial-plate. 

 The forms of both are nearly identical. They are simply wide 

 strips or ribands of the respective metals, with corrugated 

 indentations running transversely across their surfaces, and 

 bearing inscriptions as follows : — 



t&mzmifys' flail, Eontron. (goltfSmtffjs" ?£all, ILoitifflit. 



Cfjts' J^tanfrarU, commiretfofeietjen %${<& J^tantfarif, rommiretr af 



ounces' ttoo penniitDeigrjt-a at ttonttD-ttoa carats of tfinz (Sottf 



dftue jjiilber, atrtf eighteen jpemtg- anil tioa carats al Hilar) in tije 



toeigrjt* uf <Hl02j in trie jjountf pantiis toeigrjt ©roy of (great 



ioetgf)t€r0£0f (great Britain, teas' Britain, bias" macre tlje 31st flag 



maaett)e3i£t5a0 0ii©ctat)er,i829. of ©ctaoer, 1829. 



They also bear impressions from the half-sovereign die which 

 was in use at the Mint on the date mentioned, and are accom- 

 panied by certificates, signed by the then Master of that estab- 

 lishment, the Hon. J. C. Herries, and the two Assay Masters, 

 Messrs. Bingley, andBeckwith, guaranteeing their exact confor- 

 mity to standard. 



The actual trial of a Pyx, omitting the form and ceremony 

 observed, and which we may take a future opportunity of refer- 

 ring to, consists in subjecting minute portions of the plate, 



