It is one more variant of "one of lime and one of sand" ("one good and one bad; one way and the other" ) . See "give one of lime and another of sand", where in addition to the definition there is some related anecdote, and a personal interpretation of the locution.
SOME ARE MADE OF LIME AND OTHERS ARE MADE OF SAND. in colonial times it was built with lime, edge, sand and egg white as an adhesive. The lime and sand were manually moved with wheelbarrows to the point of mortar production. Some wheelbarrows were made of hydrated lime and others were made of sand. A uniform mortar was generated by a mixing process. Then small boulders were added to completely fill the mixture so that it was very compact. Hence the saying A CAL Y A CANTO, to express that something is closed to MACHOTE, hermetically. So, this expression concordantly, means of good and bad, "of everything a little". Mezcladito .
