The Sterling Hill mine in NJ sits on what is actually the strongest and largest vortex/portal on the east coast of America. It is also very similar to the superstition mountain vortex in Arizona in that it is always there but often hidden. Lately however it has been shifting and for lack of a better term amping up, the reason for the vortex type as being listed as other is because in reality all of the options apply and then some. The large zinc deposit (the ultimate manifestation mineral/stone)in addition to all of the minerals, stones, and crystals both in the museum and in storage (there are several warehouse sized buildings filled with nothing but various mineral collections) as well as the history of the place also add to the energies. In realty if you think of the vortex as a tornado The huge bottom of the tornado touches the mine itself and surrounding areas and is surrounded by 4 slightly smaller ones all stemming and joining at the top. The top itself actually covers the entire Sussex county area and parts of surrounding NJ counties as well as parts of Pennsylvania and New York state. Other smaller portals and vortexes some which are somewhat permanent others which are not, but all regularly touch down in these areas all joined up to a common top. The heart however is the Sterling Hill area.