The reign of John II. (1406-54) marks a period of exceeding confusion, coupled with inefficient attempts at legislative remedy. The disorder of his reign was further increased under his successor, Henry IV. (1454-74), years which represent the apogee of Spanish depreciation. By grants of the right of private minting the six official Spanish Mints were increased to not less than 150, with a resulting monetary disorder, dearness of necessaries, and commercial panic which it would be difficult to estimate. The gold monies varied in fineness from 23-1/2, 19, 18, 17, and so on, even to 7 quilates, and the same extraordinary variations marked the silver monies. Of billon monies there were eight distinct classes, representing a succession of fractional parts of the silver real, 1/6, 1/7, 1/8, 1/12, 1/16, 1/22, 1/24, 1/58. Taking, for the mere purpose of generalisation or average, the gold _Enrique_ of this reign at a tale of 50 to a mark, 23-3/4 quilates fine, and the silver real (= 30 maravedis de blancas) at a tale of 67 to a mark, and standard of 11.4 fine, the ratio of gold to silver for the reign would be 9.824:1. The monetary situation which the advent of the Catholic kings, Ferdinand and Isabella (1475-1506), was to alleviate and reform was the most deplorable that Spain has ever seen. Not less than eleven ordinances of reform were issued before the close of the century. For practical purposes only the first and last of these require notice. By the Mint indenture, issued on the 26th June 1475 to the Mint master of Seville, the gold coinage was ordered on the following basis:-- Excellentes (at a tale of 25 to a mark, 23-3/4 quilates fine, in value = to 2 castellanos). And silver on the following basis:-- Silver Reals (at a tale of 67 to a mark, 11 din. 4 grs. fine, in value equal to 30 maravedis). First and chiefest importance, however, attaches to the ordinance of 1497, issued at Medino del Campo, and so named. By this ordinance all the previous existing systems and monies were abrogated, and a new system instituted which forms the starting-point for the monetary history of that Spain which was to be the receiver and distributor of the gold and silver of the New World. The standard of gold was fixed at 23-3/4 quilates. The basis of the gold coins was to be the _excellente de la Granada_, issued at an equivalence of two of the antecedent excellentes, and at a tale of 65-1/3 to the mark. The system of the silver real was as in 1475, but it was issued at an equivalence of 34 maravedis, at which it ever after remained. The billon money was to consist of _blancas_ (7 grs. fine, and at a tale of 192 to a mark). One excellente = 11 reals 1 maravedi = 375 maravedis. 1 real " 34 maravedis. The changes subsequently effected in this system may be presented in skeleton form (see also accompanying Tables).