Paper Currencies vs. Gold During War Times

I just had a fascinating conversation with a 90 year old woman. Her memory isn't great on every day stuff, but her childhood memories are still sharp to the minute detail. Since Vietnam was colonized by the French at various times, they controlled the money supply (piasters). But when the Chinese and Japanese would invade, the paper money would expire worthless. Many upperclass members of society would perish, as rice was either confiscated or destroyed by the invaders.

Her mother would resort to hoarding rice, beans and grapefruit, as they were staples that wouldn't rot quickly. Some peasants survived because they had access to food (farmers), while those in the cities starved

Fortunately, her mother also hoarded gold, as her family had means. She would cut up the flattened gold with a knife, and use it to buy rice, vegetables, and fruit on the black market. One has to survive the Great Depression and world wars to recall this. Unfortunately, this is happening in real-time today in Venezuela, Argentina, and other hollowed out countries devastated by war and/or government financial mismanagement.