These coins are not actually made of Dark Matter, but they are inscribed with the words "Dark Matter" -- *and* you can spend them. In 2025, the US Mint created a series of quarters commemorating Vera Rubin, the astronomer who discovered dark matter in galaxies. On Sept. 6, 2025, the students of Earth to Sky Calculus flew them to the edge of space onboard a cosmic ray research balloon.
 
During the 3-hour flight, the coins floated  101,944 feet above Earth's surface. 
 
The coin's design features a profile of Dr. Vera Rubin gazing upward, smiling as she contemplates the cosmos. She is surrounded by a spiral galaxy and other celestial bodies. Inscriptions include “DR. VERA RUBIN,” “QUARTER DOLLAR,” “E PLURIBUS UNUM,” and “UNITED STATES OF AMERICA.” The additional inscription, “DARK MATTER," is inscribed at the bottom.
 
You can have two unbroken rolls for $199.95 (one D Mint, one P Mint). You'll also receive a greeting card showing the coins in flight and telling the story of their journey to the edge of space.