The Great Shoals is a region of icy waters and shifting sandbars above the north of the continent of Amber. This icy watery region caps the globe but does not create an ice cap. Instead wintery weather causes glacial sized iceberg that wedge onto the sandy ground.
The shifting sands and frequently shifting water depth makes shipping nearly impossible. No water based shadow paths leave the realm or arrive in the realm this way.
In general the depth of the water is in the 10 to 40 foot range, allowing waves to uncover wet sandbars. Shipping is extremely dangerous. Never the less the Navy maintains a harbor it Port Blue, though it is mostly a military base it is also a popular tourist destination for peoples of icy realms.
The Great Shoals are a rich region for pearl bearing mollusks of a great many types. Pearl Hunters endure great hardships to harvest pearls in the arctic conditions. The Amber Pearl Oysters have a mechanism to eject pearls so that killing the mollusk is not required.
Ice Pearls, a clear type of pearl, are found in these waters and are highly prized.