It was in with some tools I purchased, but I don't have a clue what it is. It's 5.5 cm x 2.5 cm x 1 cm thick.

maybe to check the size of jewels?

Sell it.

How for down do the holes go.

A one sided, 40 dot dice?

Well its Not a do-hickey, because you posted someting about them having to do with hairsprings....

How about a draw plate?

ANSWER ~ Beading Block

Hi guys, you are thing it has to do with watch repair but it is used in the jewelry repair side of the business. The beading tool forms a bead to securely hold stones in jewelry. When the tool looses it shape, you can use the "beading block" to reform the tool to be able to use it again and again.

Wow - After this 7 part answer my brain will be shot for the rest of the day.
Thomas, That was a darn good guess. The holes are the 0.0445 up to .0.059 dia. x 0.010 to 0.019 deep.
David, That's a good idea too but I think I will keep it as a nice little rectangle anvil. It's smooth on the back side and very hard steel.
Eugene. Your answer is in the answer for Thomas.
Dan, Like 6 box cars in a lopsided game.
Jack, You never can tell...
Hubert, Holes don't go all the way through.
Leon, I believe you hit it right on the nose.
THANKS ALL FOR RESPONDING.
Patrick.