GarryDenke

Stonehenge Building Materials:

85 MYA

White Chalk - The outcrop sedimentary rock of Stonehenge is Late Cretaceous Period, Santonian Age, calcium carbonate. Late Cretaceous Period outcrop sedimentary rock is the in situ construction material used by the Stonehenge builders. This material is approximately 85 million years old. This stone is called Seaford Chalk Formation rock. White in color, this building material is from Stonehenge Ditch mining area.

3100 BC

Whitestone - The oldest limestone sedimentary rock of Stonehenge is Early Carboniferous (Mississippian) Period, Arundian Age, calcium carbonate. Early Carboniferous Period limestone sedimentary rock is the first (1st) construction material imported by the Stonehenge builders. This material is approximately 340 million years old. This stone is called High Tor (Birnbeck) Limestone Formation rock. White in color, this building material is from South Wales Coalfield mining area.

3000 BC

Cosheston - The oldest sandstone sedimentary rock of Stonehenge is Devonian Period micaceous silicate. Devonian Period sandstone sedimentary rock is the second (2nd) construction material imported by the Stonehenge builders. This material is approximately 408 million years old. This stone is called Senni Beds (Old Red Sandstone) Formation rock. Green in color, this building material is from South Wales Coalfield mining area.

2600 BC

Bluestone - The volcanic rock (oldest geologically) of Stonehenge is Ordovician Period intrusive igneous diabase (dolerite) and extrusive igneous felsite (rhyolite) and tuff (basic). Ordovician Period igneous rock is the third (3rd) construction material imported by the Stonehenge builders. This material is approximately 470 million years old. This stone is called Ordovician Volcanic rock. Black in color, this building material is from South Wales Coalfield mining area.

2200 BC

Sarsen - The youngest sandstone sedimentary rock of Stonehenge is Oligocene-Miocene (Tertiary) Period silicate. Oligocene-Miocene Period sandstone sedimentary rock is the fourth (4th) construction material imported by the Stonehenge builders. This material is approximately 24 million years old. This stone is called Reading Formation rock. Gray in color, this building material is from Marlborough Downs mining area.

Garry W. Denke
Geologist/Geophysicist
Denke Oil Company (DOC)
Wildcat Station, P.O. Box 866488
Plano, Texas 75086-6488