Gem Finder: The Gem Field
Read the puzzle
A 6 by 6 grid; a number counts gems in the 8 tiles around it (diagonals too), numbered tiles hold no gem, and # is a covered tile. Row 1: 1, 1, 2, #, 2, 1. Row 2: 1, #, #, #, 3, #. Row 3: 2, A, #, #, #, 2. Row 4: B, 2, #, 3, #, 1. Row 5: 1, 1, 1, #, D, #. Row 6: 0, C, 1, #, #, 0. Which lettered tile hides a gem?
A number counts the gems in the 8 tiles around it; numbered tiles have none. Which lettered tile hides a gem?
Start with the 0 in the bottom-left corner.
B
The bottom-left 0 makes C empty. The 1 above it touches only B and C, so B holds the gem.
How to solve it
Begin in the bottom-left corner. The 0 there touches only three tiles: the 1 above it, the 1 diagonally up-right and C. A 0 means no gems around it, so C is empty.
Now look at the 1 directly above that 0, at the left end of row 5. Its neighbours are B above it, the 2 to its upper right, the 1 to its right, the 0 below and C. The numbers hold no gems and C is empty, so B is the only place for its one gem. B hides a gem.
Check the others. The 0 in the bottom-right corner touches D, so D is empty. In the top-left, the 1 in the corner touches only one covered tile, the one in row 2, column 2, so that tile has a gem. The 1 below the corner then already has its gem, which leaves A empty. That also fits the 2 in row 3, column 1: B plus the gem in row 2, column 2 make 2.
The usual slip is choosing A, because it sits beside a 2 and looks crowded. But the 1s above it pin the gem one tile higher.
Takeaway: a 0 next to a 1 often settles a tile in two moves.
Learn the method: Process of Elimination in Puzzles: Rule Out Until One Is Left
