Lodestone = magnetite, (Fe3O4) - in terms of smelting, the most iron per pound of ore, so in that sense probably very desireable to the ancient smelters, but
Hematite (Fe2O3), is not far behind, and they are often found together.
I'm sure they just used what they could get, but liked the richest ore the best.
I also think there's some info on ores in 'Persian Steel', but I can't find my copy
