Complex sentence: There are 2,600 independent businesses located in the district, nearly all of them dealing in diamonds or jewelry, most located in booths at one of the 25 "exchanges" in the district, and in a public corridor to 46th Street.
Split into simpler sentences: There are 2,600 independent businesses located in the district, nearly all of them dealing in diamonds or jewelry. Most are located in booths at one of the 25 "exchanges" in the district, and in a public corridor to 46th Street.