When reviewing modern-day currency in the United States, it is not hard to notice how most of the money people use today feature influential and historic men. Whether presidents or other political figures, these coins and bills pay homage to some of America's greatest leaders.

However, what may not always be shown in modern day currency is the influence many women have had in the development of this great nation. The U.S. Mint began a project in 2007 to shed light and pay respect to the women who worked hard to help the United States thrive and grow into the global power it is today.

The First Spouse coins are set to be released between 2007 and 2016, totaling President's spouses from 1789 to 1974. They are gold coins that complement the Presidential Dollar series also being distributed for the next few years.

Coin enthusiasts may want to collect the entire series as experts project these rare coins to hit the market with a relatively low premium, but increase in value over time as supplies become limited. Very few of these coins have been certified in perfect PF70 condition by the Numismatic Guaranty Corporation (NGC), so getting these gold collectibles from reputable gold dealers is a must.

Each First Spouse coin comes directly from the U.S. Mint and has a face value of $10. One coin contains a half-ounce of pure, 24-karat gold, making the metal worth the investment.

Collectors who want to diversify their portfolios may want to get their hands on these rare coins before they are discontinued. A full set of First Spouse gold coins can impress any future buyer, as they're the first coin series that highlights the importance of females in the growth and development of the United States.