LIMIT ONE CARTRIDGE PER COLLECTOR, trades considered.

One Cartridge, Not a Box: .600 Nitro Express by Kynoch of England, older production with “KYNOCH .600NITRO” Head-Stamp and loaded with a 900 Grain CCSFMJ (Copper Coated Steel Full Metal Jactet) projectile. I believe it is also loaded with Cordite Gunpowder.
Very Nice Patina on case and bullet, case has 3 (double) bullet crimps.

History of the .600 Nitro Express cartridge:
The 600 Nitro Express is the "Largest English*" Cartridge. It was introduced in 1899 in a (2.8" long) and later grew to (3" long): it was never a Black Powder cartridge. The 600 Nitro Express has a very large 900 grain solid projectile.
* Note: The 700 Nitro was introduced by Jim Bell, (U.S.A.) and is not technically a British cartridge, although Kynoch & H&H of England also made some 700 Nitro, it was design by Jim Bell in the USA.