4 Reales - Carlos III

Carlos III's colonial mints operated under the assayer accountability system, where the assayer's initials on each coin represented a legal guarantee of fineness — a form of personal liability backed by royal decree. Guatemala's mint, established in 1731, was one of the smaller operations in the Spanish colonial network and produced far lower volumes than Mexico City or Lima, which directly accounts for the relative scarcity of surviving examples from this period.

The KM#35.2a designation distinguishes this by assayer pairing. Guatemala issues from 1786–87 are notably harder to attribute cleanly than contemporary Mexican counterparts due to inconsistent die preparation at the Santiago de los Caballeros facility following the 1773 earthquake and the mint's subsequent relocation to Nueva Guatemala de la Asunción.