Here are our test subjects - clockwise from bottom left:

Walnut

Almond

Hazelnut

Brazil Nut

Pecan

Each of these was placed in turn on a sturdy wooden block and struck with full force by a five - pound steel sledgehammer.

The walnut exploded into an oily mist. Fragments of shell and kernel were discovered lying up to ten feet away.

The pecan (aftermath not depicted) fared little better.

The brazil nut just made a mess.

The hazelnut stayed put on the wooden block, but only in the form of a compressed pancake mixture of shell and nut.

Not appetising.

Of the five, the almond (caught here a fraction of a second before impact) came closest to surviving - the thick shell crumbled, softening the blow.

The kernel was crushed a little, but remained in one piece.

Conclusion

Well, there's a surprise - it turns out that a sledgehammer is not really a very useful nutcracker - not because it's ineffective - quite the contrary - it's too effective.

However, by holding the hammer just below the head and just making gingerly taps, it is possible to use a sledgehammer to crack a nut. Pecans were best at surviving this more measured approach

A Tougher Nut To Crack

Of course, there is one kind of nut for which a sledgehammer is a quite appropriate tool...