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

artificial lake A reservoir (; from French ''réservoir'' ) is an enlarged lake behind a dam. Such a dam may be either artificial, built to store fresh water or it may be a natural formation. Reservoirs can be created in a number of ways, including control ...

, more precisely an

excavation lake Digging, also referred to as excavation, is the process of using some implement such as claws, hands, manual tools or heavy equipment, to remove material from a solid surface, usually soil, sand or rock on the surface of Earth. Digging is actuall ...

, southeast of

Hoogersmilde Hoogersmilde is a village in the Dutch province of Drenthe. It is a part of the municipality of Midden-Drenthe, and lies about 16 km southwest of Assen. History The village was first mentioned in 1634 as Hooge Smilde, and means "high Smi ...

in the province of

Drenthe Drenthe () is a provinces of the Netherlands, 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 (province), Groningen to the north, and the G ...

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

. In 1905, Roelfsema, a

Groningen Groningen (; gos, Grunn or ) is the capital city and main municipality of Groningen province in the Netherlands. The ''capital of the north'', Groningen is the largest place as well as the economic and cultural centre of the northern part of t ...

-based entrepreneur opened a sand-lime brick 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 Lakes of the Netherlands Quarries {{Drenthe-geo-stub