As far back as the late 19th century, foundries like Griswold and Wagner were casting cookware not only out of iron, but from aluminum as well. Advertisements of the day touted polished aluminum's look of silver, such as one by Griswold Manufacturing Co, which stated, "Being solid, seamless, with no plating to wear off, it is just like solid silver in appearance."
Cooking in heavy aluminum was also promoted as being "waterless", meaning the adding of cooking liquid was unnecessary, as the cookware sealed to prevent the loss of moisture from the food. Being able to use a lower cooking temperature was also advertised, although it may have had more to do with the aluminum's propensity to warp under high heat.
The aluminum pieces typically share the same markings and design that make their cast iron counterparts attractive to collectors. In many cases, the same patterns with only minor cosmetic modifications were used for aluminum ware as were used for cast iron. Skillets and saucepans, however, are normally seen made with wooden handles, a less often-seen feature on cast iron.
In addition to pots and pans, vintage aluminum utensils such as tea kettles, pitchers, platters, ladles, scoops, and other kitchen gadgetry also enjoy collectible status.
If you've found some old cast aluminum ware with staining and oxidation in need of rehabilitation, take a look at Aluminum Restoration.
Notable vintage cast aluminum brands include:
Perhaps the most famous line of cast aluminum ware is Wagner's Magnalite. Although said to be cast from a "proprietary alloy", the name "Magnalite" likely refers to the combination of magnesium and aluminum. Magnalite evolved from Wagner Ware-branded aluminum ware which originally was cast from patterns nearly identical to its cast iron ware. With the inception of the Magnalite brand, the cookware line took on a more stylized design, including domed lids and mission-style handles. It has been written that Wagner Ware's success with Magnalite provided the wherewithal for it to purchase its largest competitor, Griswold. The brand continues today under the stewardship of American Culinary Corp.
Over the years, Magnalite design changed very little. At some point, Mission style lid handles were replaced by Bakelite knobs, and cast aluminum trivets by perforated stamped aluminum. A more plainly-styled "Country Collection" design with cherry wood handles and knobs was also produced under GHC ownership in the 1980s.
Similarly, Griswold's line of cast aluminum largely mirrored the designs of its cast iron. Griswold would go on to introduce its own more stylish Aristocraft Ware line in the 1940s, and its Symbol Ware sets in the 1960s.
Another higly-regarded cast aluminum line was that of Guardian Service Ware, instantly recognizable by its distinctively-shaped handles. Pre-1936 sold as Silver Seal cookware. Primarily sold through in-home parties. Produced until 1957. Metal lids pre-date WWII; glass later.
Other brands you may see include Super Maid, Cast-Rite, Super Health(Canadian), Master Maid, Miller Maid, Reliance, Club Hammercraft, and Miracle Maid (Advance Aluminum Castings, Chicago, IL).