Silver has been a prized metal since way back in history and attempts to make less costly simulants have been around for perhaps almost as long. Alpacca is one such alloy, a blend of copper, nickel and zinc. The formula was perfected by the Austro-Hungarian firm Berndorf (later becoming part of the German metal giant Krupp). So Alpacca Silver doesn't contain any silver at all, but is a perfected form of nickel silver which was thought to have been originally formulated in China during the 16th century and called Paktong. Over the years Nickel Silver alloys have also been known as Argentan, Albata, Maillechort, New Silver and German Silver.
Although Aplacca Silver has no real value as a precious metal it was used to produce high quality items such as this erotic Austrian Art Deco period hand enamelled case in the image (click to see listing). Items marked Alpacca are also quite scarce with the collectors market still quite niche but also competitive.