STONES of the SEASONS
The four seasons are each associated with one of the four Precious Gems. Some sources suggest alternate stones, usually with colors appropriate to northern hemisphere seasons (such as citrine or Golden Topaz for autumn).
Also see the list of modern and traditional Birthstones. For the "sign stones" which are based upon the astrological signs (constellations) of the Zodiac, see Zodiac Birthstones. For the "stones of the Bible", see Biblestones. Also see Anniversary Gift Ideas for a list of appropriate stones for any anniversary.