Your Diamond Mine page says that hypercubes get lost when the screen scrolls up, but this isn't true. They're inaccessible when they aren't visible, but if you eliminate jewels below where you had a hypercube, you can get the hypercube back. I suspect the whole screen is preserved as it scrolls up, but I haven't checked other jewels as carefully. I would have added this to the page, but it's protected from editing.
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