Dendritic agate is a type of chalcedony from the agate stone family, along with Botswana agate, fire agate, and blue lace agate, among others! While most dendritic agates have a milky body tone, they can also appear translucent to opaque. The milky base creates a beautiful contrast between the dark brown to black inclusions. 
What are dendritic agate’s inclusions made of? 
The stone’s inclusions, called “dendrites,” are a mixture of manganese or iron oxide minerals that were trapped inside the gemstone when the agate formed.
When a white agate features black dendrite inclusions, the effect emulates a striking wintery scene of snow blanketing tree branches.