"Have you been to the quarry about getting stones for your brick house",“Why aren’t you expensive A hundred catties for just three coins, and once winter arrives, they will sell for five coins.” The old man sighed: “Don’t think my bricks are expensive either; my family only earns a hard-earned living.”,He was going to the quarry to see if they also used copper coins for transactions. If so, he would take his silver and exchange it for copper coins first, then use the copper coins to pay, making a profit on the difference.。