The term 'birthstone for most Libra' can be broken down into six crossword solutions: OPAL (4 letters), TOPAZ (5 letters), GARNET (6 letters), SCALES (6 letters), SIGNS (5 letters), and SIGN (4 letters). OPAL is the traditional birthstone for most Libra, which is the seventh SIGN of the zodiac. TOPAZ is the modern birthstone for Libra, while GARNET is the alternate birthstone. The scales are a symbol associated with Libra, as it is an astrological SIGN represented by a set of scales. SIGNS and SIGN are both words associated with Libra, as it is an astrological SIGN.