Meanings of fine ironwork in English

There was a great deal of white and colored marble used and very fine ironwork was made.

However, it is not modern, and not hideous; it is quite the reverse, a study in fine ironwork.

Lofty pillars formed of cannon, superposed upon huge mortars as a base, supported the fine ironwork of the arches-real cast-ironlacework.

Lofty pillars formed of cannon, superposed upon huge mortars as a base, supported the fine ironwork of the arches, a perfect piece of cast-iron lacework.