Many people associate gold bullion bars with the bulky brick-like forms we imagine must sit in places like Fort Knox, Swiss banks, and the cartoon vault of Scrooge McDuck. But today, even in this age of electronic-fund transfers and smartphone payments, slender gold bars of a more modest scale are actively traded, hoarded, and even collected. Some of the most popular types of gold bars are Credit Suisse and PAMP, both produced in Switzerland. Gold-clad "art" bars are also sought.