Strange monolith appears in Australian bush

Deep in the Australian bush a strange monolith has appeared overnight raising suspicions that it may be connected with other mysterious monoliths appearing around the world.
It was discovered 2 days ago in the sleepy coastal hamlet of Woy Woy after a man walking his dog stumbled across it.
"I immediately thought it was a UFO or something out of this world" said the local man who wishes to remain nameless. 
Redditt users soon tracked down Google Earth imagery and discovered the object had sat there undiscovered since the late 70's and seemed to change colour every 10 years.
It's a real mystery said one local "It seems to be some sort of sculpture done by a local artist" 
Redditt users claim it may be the work of prolific artist Sydney Waters who has made dozens of similar type installations in the hills along the east coast of Australia