Erie, Pennsylvania · 1865–1957 (Erie)
Griswold began in Erie, Pennsylvania, in 1865 as Selden & Griswold, passed to Matthew Griswold's sole ownership in 1884 (later incorporated as the Griswold Manufacturing Company), and made cast iron there until December 1957. Its early skillets were marked simply ERIE (about 1880–1907). The cross-in-double-circle trademark then went through three main forms that collectors use for dating: the italic "slant" logo (about 1906–1929), the large block logo (about 1920–1940) and the small block logo (about 1939–1957). Earlier marks generally bring more money, but the pans cook the same. In 1957 McGraw-Edison bought the company and sold the Griswold housewares line that December to the Randall Company, which already owned Wagner; the Erie plant closed and later Griswold-branded iron was made at the Wagner foundry in Sidney, Ohio. Collectors treat those Sidney-made pieces as a separate, less valuable category. Erie-made Griswold has a milled, smooth cooking surface, which is the main thing that separates it from modern sand-textured iron.
Identification marks
Erie-era pieces carry the Griswold cross-in-double-circle with ERIE, PA (U.S.A.) — large block logo pans fill much of the bottom, small block logo pans have a small stamp near the centre — or, before about 1907, just ERIE and a size number. A pattern number (for example 704 on a No. 8 skillet) usually sits near the handle, often with a mold letter. Griswold-branded pieces without ERIE in the mark were generally made in Sidney, Ohio, after 1957. Reproductions tend to show rough, unmilled surfaces and blurred lettering.
12 hand-curated Griswold reference pages — every one with identification marks, common defects to inspect, and typical used price bands.

typical $90–$220
c. 1920–1940

typical $50–$130
c. 1939–1957

typical $40–$95
c. 1939–1957

typical $180–$400
c. 1920–1940

typical $35–$80
c. 1939–1957

typical $110–$260
c. 1920–1957

typical $30–$75
c. 1930s–1950s

typical $60–$160
Late 1800s–1950s (many variations)

typical $60–$200
c. 1920–1957

typical $120–$300
Early 1900s–1930s (approx.)

typical $55–$120
c. 1939–1957

typical $150–$350
c. 1880–1907