Staff at the Auschwitz Museum in Poland recently discovered that an old mug had a false bottom that hid a ring and a necklace.
"It was very well hidden," Hanna Kubik of the Memorial Collections said in a news release.
"However, due to the passage of time, the materials underwent gradual degradation, and the second bottom separated from the mug."
Tests on the jewellery found gold 583, which was commonly used in Poland between 1921 and 1931, the museum said.
The Auschwitz-Birkenau concentration camp was the site of an estimated 1.1 million murders during the Holocaust. Most of the victims were Jewish, but the Germans also killed Poles, Gypsies, Byelorussians, Ukrainians, French, Soviets and others at the camp.
While the very name Auschwitz is now synonymous with death, many of those sent to the camp were told they were being relocated with the promise of work and a new life.
That promise was a cruel ruse aimed at getting the victims to bring some of their most valuable possessions for the journey, including family heirlooms.
"In this way, the Germans were confident that in the luggage -- including clothes and items needed for life -- they would find the last valuables of the deported families,"Piotr M. A. Cywiński, director of the Auschwitz-Birkenau State Museum, said in a news release.
Cywiński said the hidden items showed that "Jewish families constantly had a ray of hope that these items will be required for their existence."Instead, they were systematically robbed and many were murdered in the death camps.
But as the new discovery revealed, the Nazis didn't get everything.
"Despite the passage of more than 70 years since the liberation of the German Nazi concentration and extermination camp, there are still cases of accidental discovery of objects hidden by the victims," the museum said.
The museum doesn't know who owned the mug or the jewelry. Read more: