1 Sol de Oro small Type, with mintmark

Peru's Sol de Oro coinage was already fighting a losing battle against inflation by the late 1970s. The small-type 1 Sol was introduced as part of a series of size reductions intended to cut production costs, but the currency itself was rendered obsolete within a few years — the Inti replaced the Sol de Oro in 1985 at a rate of 1,000 to 1, a ratio that tells you everything about what happened to purchasing power during these years.

The mintmark distinction separating KM#266.2 from its companion variety reflects Lima mint production oversight during a period when the BCR was managing multiple denominations under acute monetary pressure.