Cave Hill Diamond

John Gray discovers a unique treasure sparkling at Belfast's Linen Hall Library

Weighing in at 1 pound 3 ounces, the Cave Hill Diamond has sparkled at Belfast’s Linen Hall Library this summer. But until 2008 the very existence of any such ‘diamond’ seemed unlikely, and at best the subject of fevered Victorian imagination.

It was in the late 1880s that John Nicholson, the last of Belfast’s ballad sheet printers, published two songs entitled 'The Cave Hill Diamond'. One was described as ‘an ancient and very romantic love song’, though it appears to owe something to Sir Samuel Ferguson’s historical romance Corby MacGillmore, which had only been published in 1887. The only diamond here is Eileen O’Neill pursued by a love besotted Magennis. 

The other song, evidently a new composition as it is dedicated to Lady Shaftesbury of Belfast Castle, inhabits much the same terrain but offers us a real diamond that ‘shone by night’ on the cliffs, along with the ‘brighter gems’ of Mary’s eyes. In this case a besotted Dermoid is persuaded by Mary to climb the cliff to get the diamond and falls to his death. Here there is a declared author, Professor Robert Hanna, though he is not listed in the records of Queen’s University.

Maurice Leyden, singer and historian of Belfast folk song, was just one of those intrigued by the simultaneous appearance of two ‘diamond’ songs. In his subsequent researches he unearthed a London printed ballad of 1810 that referred to ‘all the diamonds that on the rock do grow’.

Other fragments of commentary surfaced over the years, thus the author of a piece in Ulster Saturday Night in 1895 declared ‘I know the man who found the Cave Hill Diamond’, and went on to say:

There used to be some curious stories told about the Cave Hill diamond before it was unearthed. One was that mariners entering Belfast Lough used to be dazzled by its glints and used to set their course by its brilliance. Then there was the legend that Finn McCool used to wear it on his watch guard until he dropped it.

More convincing evidence was found in Henry Bassett’s Book of Antrim (1887) in an entry for Whitewell below the Cave Hill.

Last year a very good example of the Irish diamond was found at Cave Hill by a little boy, son of Mr Hanna, belonging to Belfast. It is 11 inches in circumference, and weighs about a pound. Mr John Erskine, of North Street Belfast, purchased and advertised the crystal as the ‘Cave Hill Diamond’, finally disposing of it at a good price to the proprietors of Madame Tussaud’s Gallery.

Perhaps the Mr Hanna here was the ‘professor’ who wrote the song? Clearly at least a semi-precious stone had been found, but what was it?

Last summer the Very Reverend Norman Barr, former rector of Derriaghy, rang the Linen Hall Library to say ‘I have the Cave Hill Diamond’. The Library took an immediate interest and Barr, who had been entrusted with the ‘diamond’ and associated papers by a Mrs Kirkwood, the last surviving descendant of John Erskine, donated the material to the Library.

Certainly Erskine was the man to make much of the ‘diamond’. The Irish News in 1897 described him as a man ‘noted in Belfast for his sensational advertisements’. These were mainly connected with his ‘Military and Cap Factory’ at 84-86 North Street. As a contemporary poster put it, the wares were:

Hats, caps and tweeds, as Erskine supplied of the Royal Command of the King, the Queen, and their Royal Highnesses, the Prince and Princess of Wales, for their own wear [and] may also be had by the citizens of Belfast.

Erskine, in a rather obvious pun, named his Carnmoney house ‘Hatfield’, also the name of an historic royal palace in Hertfordshire, and he was an obsessive admirer of royalty. He inundated members of the royal family with unsolicited free gifts, and then publicised the most perfunctory replies.

His cleverest royal stunt was in 1897 when he offered seven acres of his land in Carnmoney for an Irish royal residence. The Irish News sniffily commented that this was little better than ‘three acres and a cow’ and would hardly do for a royal palace. Meanwhile the royals were perfectly happy with Dublin Castle thank you very much. 

Erskine could make his offer, certain that it would not be taken up, while he maximized free publicity. At the time of the 1904 royal visit to Belfast his North Street premises were bedecked with the slogans ‘Come back to Erin’ and ‘A Royal Residence’. Alas Erskine’s eccentric career as a self-publicist came to an end with his death in 1907.

Truth was never a central feature in his narrative, and one piece of information in that original 1887 account of the ‘diamond’ was inaccurate. He never sold the stone to Madame Tussaud’s. 

Why did he suggest that he had? Had publicity about the stone in Belfast flagged? Or had local geologists queried its significance, in which case a pretext for its removal from inspection was useful. No reference to the Cave Hill ‘diamond’ surfaces in our local learned journals though it is more than five times the weight of the famous Cullinan Diamond, otherwise the heaviest known diamond.

Perhaps our local geologists saw ‘The Cave Hill Diamond’ for what it was – quartz. Even as quartz, another difficulty arises: quartz is not natural to the geology of the Cave Hill. It can be found in the Mourne Mountains more than thirty miles away. One could, as a very long shot, argue for the possibility of transfer in ice age glacial debris. Much more plausible is transfer by human agency.

Thus the Cave Hill ‘diamond’ bears all the hallmarks of a splendid Victorian hoax, and a tall tale that took on a life of its own.

John Gray

Belfast Gems - Cave Hill and the Diamond Exhibition is on in the Linen Hall library until September 12. For more information check out the library's website.