Complex sentence: Historically, this was the standard form in which manganese was traded and used in steel making (see Bessemer process); today, manganese is usually traded and used in more concentrated form, 80% manganese content being typical.
Split into simpler sentences: Historically, this was the standard form in which manganese was traded and used in steel making (see Bessemer process). Today, manganese is usually traded and used in more concentrated form, 80% manganese content being typical.