Offered for sale: 1990 Cook Islands Silver Proof 50 Dollar coin -’50 Years of America: Christopher Columbus. 1990 COOK ISLANDS SILVER PROOF 50 DOLLAR COIN -’50 YEARS OF AMERICA: CHRISTOPHER COLUMBUS. PLEASE REFER TO ALL IMAGES. Coin condition: Silver proof, uncirculated. Silver Proof coins are higher quality than circulated coins; they are more sharply struck and are produced for collectors and those new to coin collecting. Thank You For Looking. FROM A SMOKE-FREE, PET-FREE HOME. Please check my other listings for more coins. Silver proof uncirculated 1990 Cook Islands 50 Dollar coin commemorating’50 Years of America Christopher Columbus’.