The diamonds purchased can be resold throughout the world, even in stronger currencies.
The production of diamonds is in the hands of a few large international players, who control the offer avoiding price declines.
Since they are not tied to any bank, there is no risk of losing the funds held at the failed Credit Institute.
The diamond is a movable good and can be transported elsewhere without excessive effort, if the political situation requires it.
The diamond, as a fungible asset, is the property of whoever owns it (like any banknote), or “good faith possession means title”.