The Langstane (Aberdeen)

Here’s the RCAHMS entry for the stone, Fitz. It’s not much more detailed than your own observations, but it does say that a chap called Wyness took a photo of it in the 1960s at c.NJ938060, where it was before being ‘built into the niche at the rear of Messrs. Watt and Grant’s building’ where you saw it. That can’t be far away though, because the street would hardly be called ‘Langstane Place’ otherwise? He thinks it was part of a stone circle, but RCAHMS are hedging their bets. It is apparently marked on a plan of Aberdeen by Paterson from 1746.

(F Wyness, ‘City by the grey North Sea: Aberdeen’, p280 and 292 – 1965).