The rocks are the excavated leftovers of the Boring Company’s tunneling machines. They’ll be formed into large bricks that can be interlocked with one another. Musk announced the upcoming “I know I can sell anything to my fans” sale on Twitter, saying the rock bricks will be bored on the inside to make them lighter, but still be rated to withstand California’s earthquakes. Previously Musk sold his fans Boring Company flamethrowers, and people scooped up millions of dollars’ worth of the devices. But now, rocks? I mean, come on . . .
New Boring Company merch coming soon. Lifesize LEGO-like interlocking bricks made from tunneling rock that you can use to create sculptures & buildings. Rated for California seismic loads, so super strong, but bored in the middle, like an aircraft wing spar, so not heavy.
— Elon Musk (@elonmusk) March 26, 2018