LAPIS NEPHRITICUS.	205
	learnt how, by some process now unknown, to cut it with singular dexterity and neatness into the various fanciful patterns described by the old Spanish physician. It was the " Chalchivite," the "green stone," in higher estimation than any other amongst the Aztecs, doubtless on account of its superiority in hardness to the Emerald, and which, asso­ciated with the latter, now so precious, stone, and with pearls, thickly studded the mantle of Montezuma in his first interview with Cortez. Out of this same gem was carved the elaborate clasp fastening the monarch's imperial robe ; for green was the colour appropriated to royalty in ancient Mexico. On account of this its supereminent value the old chronicler of the Conquest, Diaz, contents himself, according to his own account, with four pieces of this gem alone out of all the accumulated treasures of Montezuma in their division amongst the soldiers on the noche triste, "dis­astrous night" (July, 1520), when Cortez was forced to evacuate Mexico. Those who had burdened themselves with the golden ingots perished in their attempts to ford the breaches cut by the enemy in the long causeway leading across the lake to terra firma, whilst Diaz then and after­wards had full reason to congratulate himself upon his prudent choice. Many ages later a far ruder race, the New Zealanders, were found making the same stone the badge of sovereignty, worn by their chiefs, thrust through the lobe of the ear either in the form of a hook, or of a thick cylinder, worked perfectly even, and highly polished. Like the Mexicans, they selected for making such jewels the pure translucent green species. The coarser sort was formed with equal ingenuity and an incalculable expenditure of labour into the blades of their adzes. And here it must be remarked that the most curious circumstance connected with the history of this enigmatical mineral is the established fact