From a google search. I just typed in "Hesse crown jewels war"
The best known case of looting by American personnel was the theft of the Hesse Crown Jewels. The primary instigator of the theft was Captain Kathleen Nash. Nash, Major David Watson and Colonel Jack Durant, Nash’s lover, found a fresh patch of concrete in the cellar as they were exploring the castle. They chipped through the concrete and found zinc lined boxes full of jewels. The trio removed the jewels from the tiaras, bracelets, etc and sold them in Switzerland. In late 1945, the trio returned to the United States. In addition to the jewels and gold, the trio had looted silverware, books, and hundreds of other items. In January 1946, the jewels were reported missing by a member of the Hesse family. The Army’s Criminal Intelligence Division determined the extent of the theft and soon arrested the trio. Durant married Nash so she would not be allowed to testify against him. Watson was sentenced to three years in prison but was released after four months. His family owned a large West Coast grocery store chain that apparently had connections to people in power. Durant was sentenced to fifteen years and released after six years. Nash however, was described as a difficult prisoner and served her entire sentence of five years. About one half of the jewels had been mailed to Nash’s sister.