The Real Diamond

A traveling jeweler once arrived at Akbar's court claiming to possess the finest diamond in all the land. To prove its worth, he presented it beside a second, nearly identical stone — a clever imitation crafted from glass, so well made that even the court's most experienced jewelers could not agree which was which.

"Your Majesty," the jeweler said slyly, "if any member of your court can correctly identify the true diamond without touching either stone, I will gift it to the crown freely. If not, I ask a very generous price for both."

One expert after another examined the stones from every angle, holding them to the light, studying their edges — and one after another, they admitted defeat. The two stones appeared utterly identical to the eye.

At last, Akbar called for Birbal, who studied the situation for a moment and then asked for a simple bowl of water and two houseflies, freshly caught.

The court watched, puzzled, as Birbal placed both diamonds gently at the bottom of the bowl, filled it with water, and then released one fly directly above each stone.

The fly hovering above one diamond soon grew tired, dipped down toward the water, and landed briefly to rest — right on the surface of the stone beneath it, apparently unbothered.

But the fly above the second diamond behaved very differently. No matter how tired it grew, it refused to land anywhere near the stone below it, circling anxiously again and again before finally settling instead on the rim of the bowl, as far from that particular diamond as it could get.

"That," Birbal announced, pointing to the stone the fly refused to approach, "is your true diamond, Your Majesty."

The jeweler's face fell instantly, confirming Birbal's answer was correct.

"How could you possibly know that from a fly's behavior?" Akbar asked, astonished.

"A real diamond, Your Majesty, stays naturally cool to the touch, even underwater, because of how it holds heat," Birbal explained. "Glass, however, does not — it grows slightly warm from the light and the fly could sense that faint warmth beneath it, however small. The fly did not know it was helping us. It simply avoided what felt unnatural, and in doing so, told us the truth the eye alone could never see."

The astonished jeweler, caught in his own trick, gifted the true diamond to the crown exactly as he had promised.