"JTZ06," congratulations on your ownership of this Prussian Charles Daly gun. I would posit your gun is post-1892 based on the fact that (1) the action's water-table is stamped with the country of origin, i.e. "Prussia," in accordance to the requirement for imported products with the enactment of the 1890 McKinley Tariff Act that came in to provisional effect in the summer of 1891, together with (2) the German proof marks of 1891, and (3) the use of "HAL" [i.e. Heinrich August Lindner] over crossed pistols that replaced the earlier crown over crossed pistols that was Lindner's previous trademark stamp [The German government purloined the crown for its own use as a proof stamp.], and (4) the use of the Scott [square in cross-section although rectangular in overall shape] improved cross-bolt introduced in 1892 and later adapted for use by H. A. Lindner, which is that shown incorporated in this gun.
After the introduction of new gun proof laws and associated regulations, the German authorities wisely allowed some months for an adjustment period, in order for its domestic gunmakers to gradually come in to compliance. As well, the Scott cross-bolt was just 'introduced' in 1892 and likely took time to become known to and accepted by European gunmakers, and to be adapted for their respective uses. None of this occurred overnight, or even over the immediately ensuing months.
We do not espy an inverted Anson & Deeley brevette or patent / use number stamp on the breech face, which basic British patent for the boxlock action expired worldwide in 1889. We also see telltale ejector 'eyes' staring from the forearm. I believe the Charles Daly ejector gun was first introduced as a separate model in 1888. From informative discussions earlier read here, I believe that damascus barrels were not offered in the Charles Daly model line in the Schoverling, Daly & Gales catalogues after the mid- to late 1890's. These indicia and associated dates provide a sort of floor for the foregoing and as such help support our posited post-1892 date.
As to value, the missing horn-tip for the forearm and the resultant chip damage reduce the gun's value (and collector value) somewhat, although the condition of the rest of the gun as shown in the limited number of photographs suggest that it is in excellent condition otherwise. Unfortunately, I do not see a spectrum of revealing photographs of the wood, in order to better judge its quality and condition, and particularly have no views where wood and metal are met other than the scalloped action back. The fine damascus barrels look to be and are reportedly in very good condition.
Based solely on what I can discern from the limited photographs, owner reportage, and on recent personal experiences of buying Lindner / Daly guns in similar condition, I would put the subject gun's present market value at $4,000-4,500. If this gun were mine, by the way, I would have a replacement horn-tip fashioned and affixed, and the wood sensibly and sensitively refinished by a recognized professional. The damascus barrels would be next. These beautiful pattern-welded barrels should be re-'browned' black and white, exactly as they were finished originally. This is a first quality antique gun that is deserving of restoration and preservation.
Regards,
Edwardian