This is a Civil War era 12mm pinfire revolver manufactured in Eibar and marked "Aramburu Ermua,” identifying the Spanish maker and the town of production. Serial number 14 indicates very early manufacture. The revolver remains in good overall condition with a soft, properly functioning action. Metal surfaces exhibit an even brown patina throughout, with faint traces of original blue finish visible in a couple of protected areas. The revolver retains the characteristic features of military acquisition or private purchase. Most Aramburu pinfire revolvers were based on the French Lefaucheux pinfire system introduced in the 1850s. These revolvers used cartridges with a small protruding pin that struck the primer when the hammer fell. Spanish makers rapidly copied and adapted French and Belgian designs for export markets throughout Europe and Latin America. The exact identity of "Aramburu” is somewhat unclear because many Basque firearms were produced through networks of small workshops rather than large factories. In some cases, Aramburu appears to have been a distributor or merchant name rather than the actual manufacturer. One historical reference connected to the Orbea Modelo 1884 mentions a Joaquín Aramburu acting as a Madrid firearms dealer for Smith & Wesson revolvers in the 1870s. Like many Eibar-made revolvers of the period, Aramburu-marked pinfires were typically handcrafted in small batches. Quality ranged from crude utility arms to surprisingly well-finished pieces with engraved frames, folding triggers, octagonal barrels, and ivory or walnut grips. The Basque gun industry thrived because Spain’s patent laws were relatively loose, allowing local makers to reproduce successful foreign firearms designs. By the 1880s and 1890s, pinfire revolvers were gradually replaced by more modern centerfire cartridge systems. Many small Spanish makers either shifted to cartridge revolvers and automatic pistols or disappeared entirely. However, surviving Aramburu pinfire revolvers remain collectible today as examples of the early Basque arms trade and the industrial gunmaking tradition of Eibar, which dates back several centuries