“...The agate site near the small town of Souris in Southwestern Manitoba is special in more ways than one. It is a secondary agate-deposit.
The agates themselves were brought from enormous glacier flows about 42,000 years ago, which penetrated from the Rockies to the northeast to Manitoba. Most of them are looking like the agates of the "Montana agate type". So their origin may be accepted somewhere in the area of the present-day southeastern Montana...The surface of the specimen is generally rounded, sometimes really "natural tumbled". Inside, the most colorless and grey-yellowish, weak banded agates are “look-alikes” of those from Montana. Inclusions of beautiful black or brown dendrites, mossy-like structures and plume and rather small-scale colourful places in black and dark orange inside of the banding are given its own charm to the specimen..."
Johann Zenz in his book "Agate" (2005 bode publishing house).