Blazon: Per pale gules two cauldrons in pale chequy or and sable, each containing twelve serpents, eight facing the exterior and four facing the interior proper and chequy of twelve argent a lion rampant purpre armed and crowned or, langued gules (León) and gules a castle triple-towered or windowed azure (Castile)
Blazon: Per pale I per quarterly i and iv gules a castle triple-towered or windowed azure (Castile), ii and iii argent a lion rampant purpre crowned and armed or, langued gules (León); II azure a castle triple-towered or windowed of the field on a mount in base proper, in chief a molet of eight points argent
Blazon: Vert a castle triple-towered or windowed gules between two lions rampant combatant of the second, langued of the third, in chief a double-headed eagle displayed and in base a lamb passant argent
The motifs of the castle and the lions are extremely popular in Spanish municipal arms as a reference to the twin kingdoms of Castile and Leon. Unfortunately, I cannot find any information on the potential origins of the eagle or the lamb.