Here the yellow trail markers are more scarce but there is orange flagging tape to guide you. You're on the Bluff Adventure Loop, a 1km diversion from the yellow trail along the coast. Don't go too near the edge - if your coordinates take you to the edge STOP and look for a spruce tree. These caches are meant to bring you to this area, not to be difficult to find.
This cache is placed along the Yellow Trail of the Black Rock trail system. http://blomidonnaturalists.ca/kings-county-nova-scotia-hiking-nature-trails/black-rock-community-hiking-trails/# While the literature states the trail is difficult, I would rate it as moderate. It is very important to follow the trail markers; not doing so could easily get you lost.