Grand Lama

Once upon a time there was a Grand Lama who had a chessboard made of pure gold, magnificently engraved, and, of course, of great value. 
Every year a tournament was held at Lhassa among the priests, and whenever any one beat the Grand Lama it was considered a great honour, and his name was inscribed on the back of the board, and a costly jewel set in the particular square on which the checkmate had been given. 
After this sovereign pontiff had been defeated on four occasions he died possibly of chagrin.

The new Grand Lama was an inferior chess-player, and preferred other forms of innocent amusement, such as cutting off people's heads. 
So he discouraged chess as a degrading game, that did not improve either the mind or the morals, and abolished the tournament summarily. 
Then he sent for the four priests who had had the effrontery to play better than a Grand Lama, and addressed them as follows: "Miserable and heathenish men, calling yourselves priests! 
Know ye not that to lay claim to a capacity to do anything better than my predecessor is a capital offence? 
Take that chessboard and, before day dawns upon the torture chamber, cut it into four equal parts of the same shape, each containing sixteen perfect squares, with one of the gems in each part! If in this you fail, then shall other sports be devised for your special delectation. Go!" 
The four priests succeeded in their apparently hopeless task. 
Can you show how the board may be divided into four equal parts, each of exactly the same shape, by cuts along the lines dividing the squares, each part to contain one of the gems?

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Math Genius