A rare-coin dealer’s wife named in an indictment for money laundering last May reached a plea agreement Thursday.

Denise Gunderson Rust, who allegedly helped her husband, Gaylen Dean Rust, run a $200 million Ponzi scheme attempting to defraud investors with a fake silver trading program, pleaded guilty to one count of money laundering, according to the U.S. attorney for Utah.

Denise Rust’s possible sentence could be 18 months in prison on the high end or five years’ probation on the low end. She has also agreed to pay upward of $1.7 million in restitution, but the exact amount will be decided at a sentencing hearing yet to be scheduled.

Gaylen Rust, the owner of Rust Rare Coin, and his son, Joshua Daniel Rust, are charged with wire fraud and money laundering conspiracy. Gaylen Rust is also charged with two counts of securities fraud, while Joshua Rust is charged with one count of money laundering.

The indictment alleged that from 1996 to November 2018, Gaylen Rust conspired to defraud people by offering them stock in a silver trading program, using money from later participants to pay back the promised return to early investors. The money was never used to purchase silver, though, according to the court documents, and there was never any silver placed in depositories.

Instead, the family spent the extra funds on thoroughbred horses, authorities said.

Additionally, Gaylen Rust was not licensed to sell or trade commodities. The family was also accused of creating fake account statements. Gaylen Rust is being sued by some of the investors.