Long Table 210. The Milled Pillar Coinage of Mexico City—A Historical Undertaking

As the Spanish Habsburg dynasty gave way to the House of Bourbon in 1700, sorely needed political and economic policy reforms were imposed upon the Kingdom of Spain. The advent of milled coinage in the Spanish New World Colonies, starting with the Mexico City Mint, introduced a new minting method and a highly symbolic coin design that would circulate worldwide. Brad Yonaka (four-time author and specialist in Spanish colonial coinage) explores the so-called ‘Bourbon Reforms’ from a numismatic perspective.

[DB-oune]

the question of why .9166? Isn't that just 22 carat? 22/24 =