A hundred grams, brought back by a robot

Luna 16 drilled thirty-five centimetres into the Sea of Fertility, sealed the core in a capsule, and flew it home — the first sample return from another world without anyone aboard.

It came back with about 101 grams, against Apollo's hundreds of kilograms, but it came back thirteen months after Apollo 11 and cost a fraction as much. A gram of it was swapped with NASA for Apollo material, and some was auctioned in 1993 for close to half a million dollars.