10 Réis and 20 Réis Coins of King Luís I (1861‑1889)
The 10 Réis and 20 Réis coins of King Luís I (1861‑1889) form part of the lower‑denomination issues of the period and are divided into two distinct monetary systems. The first system, struck in copper between 1867 and 1874, includes the larger‑module coins bearing the Roman‑numeral denominations X Réis and XX Réis. The second system, minted in bronze between 1882 and 1886, introduced the reduced‑module versions of both values, reflecting the technological transition and evolving minting standards of late 19th‑century Portugal. Although the coins display Roman numerals, they are commonly referred to as 10 réis and 20 réis in modern numismatic terminology.