South African units

Hello. I have just found and joined this great website. I am researching several of my ancestors who fought in the Boer War, one being Sergeant Isaac Barton No. 2908 2nd Manchester Regt. Mounted infantry. He was awarded the DCM, QSA (4 clasps), KSA as well as Long Service and Good Conduct Medals. I have discovered from this website that:- "The Johannesburg and Diamond Hill clasps are very rare to the Manchester Regiment. The Manchester Regiment gained the award of 27 D.C.M's. during the Boer War, just two of which were to the Mounted Infantry. DNW Sep 04 £2,100". I would be interested to hear from anyone who can tell me why he would have got the 'extremely rare' clasps? It would also appear that his medals were sold by 'DNW' in 2004? Is it possible to get a picture of these; contact the seller; contact the purchaser? Looking forward to your responses. Tony