Chapter 578: Song Jin_2

"Although stone is not as valuable as iron ingots, it's still a very precious resource in the first-order. How much money did you spend on such tall and thick stone walls, and the twenty upgraded tower archeries, junior?"

Looking at Zhang Yan's defense facilities and civilization units, everyone was greatly shocked and amazed.

Zhang Yan shook her head and said with a smile, "This is a rare territory. There's a small spirit stone vein in the valley from which we can extract spirit stone resources."

"Spirit Stones?"

The crowd's eyes narrowed, and they exclaimed, "Are those the rare high-level resources needed even by high-level lords?"

"Yes!"

Zhang Yan nodded and continued, "I handed over the extracted spirit stones to the student council, and with the support and overdraft from the student council and the Ninth Campus, I bought the civilization core of the Great Song Dynasty."