A first edition of the facsimile of the 16th century codex maintained at the Torre do Tombo National Archive. Published in 1956, it quickly sold out and became a work of great rarity. Undeniably beautiful, commissioned by King Manuel, the Livro do Armeiro Mor is dazzling for its 128 illuminations by the King of Arms, Jean du Cros. This armorial - a compilation of the heraldic arms - is of great historical importance making contributions to genealogy, heraldry, and diplomacy. The work is so named because it was entrusted to the care of the Master Armourer Álvaro da Costa, remaining in his family for over ten generations. In fact, this would be one reason why the Livro do Armeiro Mor escaped the Great Earthquake of 1755, which destroyed, among many others, the Noble Archives. It is, therefore, the oldest armorial to survive to our times, having served as the basis for later publications. This copy, with its leather binding embossed in gold, evokes a world of colour, light and arabesques that guides the reader back through the reign of Manuel the Fortunate. Considered a true masterpiece of the Portuguese enlightenment, its artistic and cultural value is equalled only by codices such as the Apocalypse of the Monastery of Lorvão (1189), the Bible of the Jerónimos (15th century) or the Book of Hours of King Manuel (c. 1517-1538).