The size is perfect for carrying ina pouch or in your pocket!  The prices for each heart is listed below.
 
Left to right:
Malachite (Heart Chakra Healer) - $6.00 
Quartz (Amplifier) - $4.00
Jade - (Prosperity Stone) - $4.00
Labradorite (Creates Magic) - $4.00.
 
Size:  All hearts pictured are approximately .63" x .63" x .5".