"Amor, Honor et Justitia" - Google Search shows that this motto is linked to the Bayard family in USA, the Limerick Masons Guild and the
Royal Masonic Institution for Boys - 1977 medal
(Justitia, also called Persephone, is Minerva’s name when she judges the dead in Hades).
In heraldry the simplest version of a design is the oldest and this appears to be an early variation of the arms of a Guild of Masons.
This simple chevron could even be read as a working square
derived directly from the fr. chevron, i.e. rafter of a roof.
stemma araldico in nero su bianco recante 3 torri, 2 in alto ed una in basso, separate da un compasso aperto.
those of the Masons Company, a plain chevron and three Towers.
the clear similarity in the forms of their heraldic arms: the Carpenters having three dividers or compasses around an engrailed 'chevron' (fig. no. 5),
whilst the Masons had three castles or towers around a similarly engrailed chevron on which a pair of compasses is displayed (fig. no. 6).
What is even more singular is that on an earlier form of the Carpenter's arms we see the central chevron bearing a working square and what looks remarkably like a primitive skirret with its string (fig. no. 7).
Sotto, in bianco su nero, il motto su cartiglio: "AMOR HONOR ET JUSTITIA
a better description might be:-
an arm in armour embowed to the sinister holding a sword
I have not found an example sinister but dexter is seen in several irish or scottish arms.