Note, if a numbered stone is broken and two separate bits or fragments of it are visible then it counts as two stones etc.
I have checked this on the ground, but errors may remain, please comment if you spot any.
|Stone No.||Volume (m³)||Estimated above ground weight (tonnes)||Additional visible fragments|
|80 Altar Stone||1|
|Total Visible Stones 93|
Click to enlarge - from http://upload.wikimedia.org/wikipedia/commons/thumb/7/7f/Stone_Plan.jpg/967px-Stone_Plan.jpg
Stone 40g is not counted because all that is visible is a lead cap.
There are five Sarsen Trilithons which gives fifteen large Sarsen stones.
The outer ring of Sarsens is planned to contain thirty uprights and thirty lintels so that is 75 worked sarsens in total.
There are four sarsens outside the centre, the two Station Stones, the Slaughter Stone and the Heel Stone.
There are stoneholes for other stones matching these, another two station stones, a matching Slaughter Stone and a paired hole to the Heel Stone. (There are other holes such as the F,G and H holes which maybe were stoneholes.) These empty holes may have held other stones or maybe stones that were then moved, for instance the Heel Stone may have originally occupied Stonehole 97. So that is between five and ten other sarsens.
There is the Altar Stone, origin unknown.
And lots of bluestones and bluestone holes. There are 29 bluestones that are still visible, but the original number is probably around 80. They have been shuffled around the holes so it is hard to be sure but that is a reasonable estimate.
So Stonehenge may have had up to 165 stones originally. It also had a vast number of stone fragments and hammerstones used for packing.
Where are the missing stones from Stonehenge?
We don't know.
There is broken up bluestone, known as debitage, all over the site. Is this from stones being broken up for tools and talismen or is it the remains of shaping the stones?
We know bits have been knocked off the edges of stones, greatly reducing them in some cases but complete stones carted off for use elsewhere have not been found despite searches. So it is another Stonehenge mystery.
(Note this is an updated post combining previous published posts into one.)
April 2020 - Note from http://www.stonesofstonehenge.org.uk/p/missing-stones.html
Some bluestones and bluestone fragments that are labelled on the plan, for example Stones 32c (Type: Altered Volcanic Ash), 32d (Type: Spotted Dolerite), 32e (Type: Rhyolite), 33e (Type: Altered Volcanic Ash), 33f (Type: Altered Volcanic Ash), 40c (Type: Calcareous Ash), 41d (Type: Altered Volcanic Ash), 42c (Type: Sandstone with Mica), 70a (Type: Spotted Dolerite), 70b (Type: Unknown) and 71 (Type: Unknown),.... are not visible above ground level and exist only as completely buried stumps.