This is the north stone of the gate. You can see the hand drilled hole at the center. Other holes have caused the rock to split. 
This is the south side of the gate. The one block of Jade is sitting flat below and the other is the one standing up in front. The bottom block of jade is about 15 tons, while the upper block is about 10 tons. 

The Megalithic gate has some of the largest stones at the site. The one side consists of two large blocks of Nephrite Jade. The one is about 10 tons and the other is about 15 tons. They appear to have been once stacked one upon another. The other side of the gate is a 15 ton white crystalline stone that appears to be perhaps peridotite. The white block, the north side, has been drilled in several places and now lies in pieces. The gate lies to the north side of the ditch that traverses the complex. Where the blocks of stone that make up the gate come from is a mystery. Nephrite Jade is not commonly found in Ontario. The other stone has a thick fusion crust and so is not weathered, or shaped by glaciation.