Expert Life-Shapers among the elves know the secret of shaping “ironwood,” a weblike growth of massive trees that, as it sounds, are purported to have the strength of iron, capable even of holding an edge like steel. “Ironwood” is an aspect that each such weapon and invoked when its special qualities might come into play.
When used to replace metal equipment, ironwood is not especially better or worse than conventional materials except in specific circumstances (ironwood might be more prone to absorb moisture unless properly sealed, for example, and in extreme temperatures it would ignite rather than melt). However, when used to construct wooden items, ironwood has many of the properties of a harder, heavier metal item instead, and might exhibit some different properties based on that; an ironwood cudgel would be more equivalent to a steel mace than a wooden club, and an ironwood bow would be incredibly difficult to draw, like trying to make a bow from an iron bar.
The purchase difficulty of an ironwood item is 1 higher than the same item of a more conventional material, though in areas dominated by elves, ironwood might represent the norm, while tools of iron would be more costly.