The Blauwe Meer ( Dutch for "blue lake") is an

artificial lake A lake is often a naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from t ...

, more precisely an excavation lake, southeast of Hoogersmilde in the province of

Drenthe Drenthe () is a province of the Netherlands located in the northeastern part of the country. It is bordered by Overijssel to the south, Friesland to the west, Groningen to the north, and the German state of Lower Saxony to the east. As of Jan ...

Netherlands , Terminology of the Low Countries, informally Holland, is a country in Northwestern Europe, with Caribbean Netherlands, overseas territories in the Caribbean. It is the largest of the four constituent countries of the Kingdom of the Nether ...

. In 1905, Roelfsema, a

Groningen Groningen ( , ; ; or ) is the capital city and main municipality of Groningen (province), Groningen province in the Netherlands. Dubbed the "capital of the north", Groningen is the largest place as well as the economic and cultural centre of ...

-based entrepreneur opened a sand-lime

brick A brick is a type of construction material used to build walls, pavements and other elements in masonry construction. Properly, the term ''brick'' denotes a unit primarily composed of clay. But is now also used informally to denote building un ...

factory at Hoogersmilde, producing a cheaper alternative to traditional fired brick. The Blauwe Meer was formed by quarrying the sand needed for the brick. It takes its name from

glauconite Glauconite is an iron potassium phyllosilicate ( mica group) mineral of characteristic green color which is very friable and has very low weathering resistance. It crystallizes with a monoclinic geometry. Its name is derived from the Greek ...

that, along with its depth, gives its water a blue-green tint. Today it used for bathing, with controlled water quality.

References

Artificial lakes of the Netherlands Quarries {{Drenthe-geo-stub