They look like
billon aspron trachys, indeed from the Latin rulers of
Constantinople.
"LATIN RULERS OF
CONSTANTINOPLE. (1204-1261)
Billon aspron trachy, small module. Large
cross I-C-X-C (arranged clockwise) in angles / Emperor standing facing, holding sword and
labarum.
Sear 2043"
However another interpretation of the letters in the angles as listed on
Wildwinds is I-C-N-K, as in:
"Latin Rulers of
Constantinople. 1204-1261. AE small module
Trachy. I C N K in the four angles of a
cross on a base / Emperor, full length figure, standing, holding long spear and
cross on globe.
Sear 2054"
I believe they are somewhat
scarce and yours are in nice condition.
