British Museum. Department of Coins and Medals, A Guide to the Exhibition of English Medals
“ The work of Thomas Simon was not confined to medals, for he executed all the Seals for the Commonwealth and for Charles II., as well as a fine set of coins which bear the portrait of the Protector. His last work of this kind, the Petition Crown of Charles II., has never been equalled in technical delicacy of execution, and is certainly the finest coin of modern times. Thomas Rawlins cannot be mentioned in such high terms as the Simons. His work was far above the average; but it failed to attain the sharpness and high finish which characterise that of his two rivals. ”
