Armourer's Mark: Proof that quality control is nothing new

Charles Ffoulkes in The Armourer and His Craft From the XIth to the XVIth Century (1912) stated that the mark or poinçon of the armourer "invariably means that the piece is of good workmanship and worthy of notice." The armourer's guild was no different than the other Medieval craft guilds. It was very jealous of the repuation of its members. In fine suits of armour one will find that the individual pieces that make up the harness will all be stamped with the maker's mark and, in the case of German and Burgundian work, often that of the town as well.

The secrets of armouring were well guarded and never written down. Even today, there are aspects of the art that we do not fully understand. A master would only impart his knowledge upon his apprentices. An apprentice would have to prove his ability before being allowed to make an actual piece of armour. He would not make an actual harness from head to toe, but instead only make one or more individual pieces. The work would be carefully monitored by the master, who would place his mark on it only if it met his approval. In time, he could become recognized as a journeyman armourer. Only a select few would ever achieve the rank of master armourer. In the major armouring regions like Milan, it seems that entire towns would sometimes have been employed to make source material such as links for mail.

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It appears that from a very early period in plate armour-making there was a system in place of proving armour using the weapons most commonly in use at the time. Even mail seems to have been proof against arrows at a very early period. While my understanding of Latin and French is derisible, I have been able to find translations of period documents that show that armour was proof against a wide range of attacks. According to Ffoulkes, in the Chronicon Comariense, under the year 1398, there is a statement that the men-at-arms wore armour that negating the wounds of the bow. There are other documents that have definite entries of arrows used for proof, which would naturally have had exceptionally well-tempered points (Reg. de la Cloison d'Angers, No. 6 (1378)). There are entries for such projectiles in 1419 costing 8 shillings per dozen, while ordinary arrows cost only 4 shillings per dozen. Ffoulkes goes on to explain the regulations of setting proof marks on armour. The bottom line was that the wearer would pay handsomely for the very best protection only if it worked, and so the armourer put his reputation on the line.

1347. Regulations of the Heaumers of London (original in Norman-French), City of London Letter Book, F, Fol. cxlii. Also that helmetry and other arms forged by the hammer...shall not from henceforth in any way be offered for sale privily or openly until they have been properly assayed by the aforesaid Wardens and marked with their marks.

The notation "de toute botte" suggests that the armour was proof against all blows (sword, axe, etc.) and also to the bow and crossbow. During later centuries, the terms "high proof" and "caliver proof" and "musket proof" referred to protection against period firearms and appeared often in writings up to the time that armour was eventually discarded. In the case of brigandines, coats of armour that consisted of a series of overlapping metal plates riveted together between two layers of cloth, each of the small plates were often individually stamped with the maker's mark as evidence of proof.

Source: The Armourer and His Craft From the XIth to the XVIth Century, Charles Ffoulkes, 1912.