There's one for each month, with a special limited edition also available for the month. If you pick up a gemstone phoenix, put your name in the box in Raglan Shire with your name and RL or SL birthday and receive a special gift on that day
. They make great gifts, too...you can also put a friend's name in the box if you bought it for them and they'll get the gift 
Since my vendor broke they're only available in Raglan Shire, The Wild Things Mall and Wizard's Alley! (They make great wizard familiars!)