The silver one shilling coin was made in Boston in 1652, and is one of about 40 known to still exist, a Rhode Island coin expert says
PMR - 2024 #2 March/April by Professional Coin Grading Service
ANS Digital Library: Mark Newby's St. Patrick coinage
$20 Pure Silver Coin – Commemorating Black History: Amber Valley
Rare coin made in Colonial New England could fetch $300,000
German Coins
Buying and Selling Rare Coins at Northeast Numismatics
Exonumia Coin News
Rare coin made in Colonial New England could fetch $300,000
Rare coin made in Colonial New England could fetch $300,000 at UK
Buying and Selling Rare Coins at Northeast Numismatics