'Shekels' in the Bible

So the king of Aram said, Go then; and I will send a letter to the king of Israel. And he went, taking with him ten talents of silver and six thousand shekels of gold, and ten changes of clothing.

And they became very short of food in Samaria; for they kept it shut in till the price of an ass's head was eighty shekels of silver, and a small measure of doves' droppings was five shekels of silver.

And Menahem got the money from Israel, from all the men of wealth, fifty silver shekels from every man, to give to the king of Assyria. So the king of Assyria went back without stopping in the land.