The feature was named by the Alberta-British Columbia Boundary Commission in 1921, in association with Gateway Peak.

While on the summit of Mt. Postern I made an interesting discovery, namely, that Gateway Glacier as shown on the Interprovincial Boundary Sheet No. 28, is not glacier at all, but a lake! This lake, which is of a beautiful jade colour appeared to be quite a bit larger than Icefall Lake and will, I hope, eventually take its place on the map as “Jade Lake.” It should be mentioned that Jade Lake lies a in a deep cirque between Mts. Portcullis and “Warden” and is invisible from any of the survey stations.

— Wates and Gibson