This is one of those sites that make a single site-type classification system very restrictive, for this is really a decorated standing stone ... and a mighty fine one it is too!
The stone itself is a little over 2m tall and 1m wide and is aligned SW-NE. It is the SE side that bares all the decoration, which includes many cup-and-ring motifs as well as simple cup-marks. One of the designs is very unusual in that it is made up of two cups surrounded by a kidney-shaped ring.
The ornamentaion is worn on the bottom left hand side of the stone as you face it, which I think must have been caused by it having been used as a rubbing post at some point.
The views are quite extensive over Lough Foyle to County Derry, but the presence of a new house just 200m away does dampen the atmosphere a little.
This is an explanation of (and a bit of a disclaimer for) the coordinates I provide.
Where a GPS figure is given this is the master for all other coordinates. According to my Garmin these are quite accurate.
Where there is no GPS figure the 6 figure grid reference is master for the others. This may not be very accurate as it could have come from the OS maps and could have been read by eye. Consequently, all other cordinates are going to have inaccuracies.
The calculation of Longitude and Latitude uses an algorithm that is not 100% accurate. The long/lat figures are used as a basis for calculating the UTM & ITM coordinates. Consequently, UTM & ITM coordinates are slightly out.
UTM is a global coordinate system - Universal Transverse Mercator - that is at the core of the GPS system.
ITM is the new coordinate system - Irish Transverse Mercator - that is more accurate and more GPS friendly than the Irish Grid Reference system. This will be used on the next generation of Irish OS maps.