I think that your friend has this weapon (my best guess from internet search; I know little about revolvers from this era):
From Australian/New Zealand military history website...
http://www.diggerhistory.info/pages-weapons/00-weapons-cat-index.htm
1890. Belgian six shot, break open, double action revolver by Arnant.Fransouet. The frame and cylinder are nickel plated with floral engraving. The horn grips also have a carved floral design. The barrel is engraved U.ARNANT.FRANSOUET Bte and a Belgian proof mark is stamped on the cylinder. The frame has a double clip action release and a lanyard ring on the butt cap. The pistol is contained in a British brown leather service holster that is missing the top strap and stamped 2829 on the front.
It has single belt loop at the rear. Barrel length: 140 (mm); Calibre: 11 (mm); Overall length: 270 (mm). This revolver was taken from a German officer during the First World War. It was in the possession of a member of Woy Woy R.S.L. Association who asked to have it sent to Australian War Memorial.
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Alternatively, it could be an indigenous knock-off of the above Belgian revolver or even (possibly) this one...
http://www.rememuseum.org.uk/arms/pistols/armpr.htm
Commonly known as the Pryse's Army Revolver (.45), it is a Webley made pistol patented by C Pryse in November 1876. It was a great favourite with Army Officers and has the distinction of being the first pistol to have a rebounding hammer (ie one in which the hammer, after striking the cap, rises far enough to be withdrawn from contact with it). It is sometimes called the 'Chinese Webley' due to the fact that the Chinese Government bought large quantities. It is said that the popularity of this pistol started Webleys, who were then emerging from the doldrums due to the success of their 'RIC' (Royal Irish Constabulary) revolver, on the quest for a really first class 'Break-down' self-ejector, which of course they eventually achieved. This particular pistol was sold by Henry of Edinburgh and London (Martini-Henry fame).
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Almost every firearm under the sun has been directly copied (often individually hand-crafted) by Pakistani gunsmiths in the Peshawar / Waziristan region. This could be something similar...