FOILCheapest priced copy (Breaking News): $4.49 at Card Kingdom, near mint, their price list as of .
Grindstone 
Artifact · Special · Kaladesh Inventions · #39
{3}, {T}: Target player mills two cards. If two cards that share a color were milled this way, repeat this process.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
6 printings · $4.49 to $159.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Kaladesh Inventions | 39 | Special | — | $159.99 |
| Breaking News | 62 | Mythic | $4.49 | $6.99Out of stock |
| Breaking News | 79 | Mythic | — | $59.99 |
| Judge Gift Cards 2023 | 2 | Rare | — | $19.99Out of stock |
| Tempest | 290 | Rare | $12.99 | — |
| World Championship Decks 1998 | rb290sb | Rare | $8.99 | — |
2 rulings from Wizards of the Coast
- 4 October 2004If the two cards are both colorless, then the effect does not repeat. It only repeats if both cards have at least one color and at least one color is shared between them.
- 12 April 2024The process can repeat any number of times, as long as two cards that share a color are milled each time.