I have really enjoyed researching the symbolism for December. The narcissus and mistletoe have been done, and now the holly: In many ancient cultures it has been a symbol of the waning solstice, which ends at the winter solstice - the shortest day of the year, when it begins to wax again. The Druids believed that the evergreen nature of the holly made it sacred, as it remains green throughout the winter and keeps the earth beautiful. Holly was used for decoration throughout homes with its being used for boughs over entrances or for wreaths on doors. This custom originated in Ireland, since holly was one of the main plants that was green and very beautiful with its red berries at this of year, and gave poor people a means of decorating their dwellings. It was also believed to give the inhabitants of such a dwelling prosperity and peace for the coming year.
As for the turquoise, throughout history and in many cultures, it has represented the earth and sky, and protection of the body and soul. For a really really interesting read on this, click on this link and enjoy! (go to "spiritual belielfs and symbolism) As this beautiful stone is found all over the planet, many cultures have spiritual symbolism attached to it.