Many consumers and financial planners use third-party grading or certification services to verify grade gold coins before they buy. These services "certify" coins as to grade and usually encapsulate them in a "plastic" holder with some form of grading certificate or "slab." However, consumers can lose money even when a certification or grading service is used. Certification services provided by dishonest coin dealers too often are part of fraudulent sales schemes and are intended to mislead consumers. In some instances, even certificates or slabs from legitimate services can be misleading. For example, some certification services use looser standards than those generally accepted by dealers in the rare coin market. As a result, the coins they certify may be worth less than other coins of the same grade. There are special pricing publications and sight-unseen trading networks for coins certified by major services. Before you buy any certified coin, make sure that you check its current value in one of these sources. Some fraudulent sellers may use an old certificate to mislead you into believing that a coin's grade is accurate by today's standards. Check the date of any certificate or slab you are offered and investigate the certification service before you commit to a purchase.

Compare different web sites about coins to learn as much as possible before investing in gold coins.