The bone is the last and best bit of a joint , A.K.A. stinging roger or roach. To be a true stoner you must smoke every joint to the bone or you qualify as a massive pussy. To bless the joint you can put a polo ring around the roach to make it a holy joint.
The Bone Zone is used by yelpers as a euphemism for sex. The claims often seem dubious, as it is hard for one to imagine anyone wanting to sleep with the people who use the phrase most often.
There are reviews of the Bone Zone on Yelp's New York page, because it is important to let the world know that you are getting some.