rod iron, rot iron/wrought iron
Wrought iron has been worked (wrought) by hammering and bending, often into elaborate shapes. It is distinguished from cast iron, where the iron takes on the shape of the mold the molten metal was poured into.
There is such a thing as “rod iron”—iron shaped into rods—but this is a rare specialized term. Most instances of this form are erroneous spellings of “wrought iron,” as are all instances of “rot iron.”
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