Steel has always been the material of choice for fine crochet hooks used for thread work. During the first century of crochet (about 1840 until 1940) steel crochet hooks underwent many changes in design and style due largely to advances in steel manufacturing techniques before settling on the steel rod with flat (grip, pad) design most prevalent today.
The following chart shows a general overview of how advances in steel manufacturing influenced the design of steel crochet hooks. Advances are summarized in red along the left side. Patents are used to fix the starting date for new techniques. As with most manufactured products, the goal is a better product made faster and cheaper.
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