"What can you do with glass?" Su Hao asked rhetorically.

Hao Qing didn't understand what Su Hao meant, and he said cautiously: "This glass is generally nothing more than three uses. One is to make tiles, the second is to make bottles and cans, and the third is to make glass beads. However, the utensils made of this glaze look very gorgeous at first glance, but in fact they are not suitable, not as heat-resistant and bump-resistant as porcelain. ”

Su Hao said: "I heard Hao Tong say that you have a colorless and transparent glass product at home, can you let me open my eyes and appreciate it?" ”

Hao Qing nodded, and shouted loudly to the room in front of him: "Little Wuzi, go to our shelf and bring the translucent glass bowl, and ask Master Su to take a look." ”

The little five sons in front of him agreed, and after a while, he came over with a transparent glass bowl. He handed the bowl to Su Hao and said, "Master, please take a look." ”

Su Hao took the bowl and looked at it, and was really a little shocked. I saw that this bowl was really made of colorless transparent glass, which looked crystal clear. The most rare thing is that the thickness of the wall of the glass bowl is very uniform, which reflects the skill of the maker to blow glass. The edge of the bowl is obviously polished and polished, without a little edge and corner, and it is very smooth to the touch, which is really a fine product in terms of the craftsmanship level of the Ming Dynasty.

"Is this glass bowl made by Brother Hao?" Su Hao asked.

Hao Qing nodded and said, "It's made by Xiao Jin." Xiao Jin's skills are not refined, but it makes the master laugh. ”

What he said was that his skills were not perfect, but the expression on his face was clearly quite proud. In those days, it was a rare skill to be able to make glassware, let alone to be able to make them so delicately, and in that respect he did have the capital to be proud.

Su Hao felt a little happy and a little disappointed in his heart. The joy was that he was able to find glass relatively easily, and that there was a very good glass craftsman, so he didn't have to think about the craftsmanship again. The disappointment was that he originally planned to make some money by burning glass, but now it seems that he still underestimated Gu Jin's ability.

"Brother Hao, what I want is some thick colorless translucent glass sheets, round, and then polished, some to be ground into the middle thick and thin around the perimeter, and some are the opposite, to be ground into the middle thin and thick around the perimeter. Do you think you can make such a glass piece? Su Hao asked.

Hao Qing frowned and said, "I can do it, but I don't know what is the use of Master Su asking for this kind of glass piece?" ”

Su Hao smiled: "What is the use, I can't reveal it yet, but I believe that after Brother Hao grinds out the glass piece, he will be able to understand." What I want now is Brother Hao's accurate words, whether it can be done. ”

Hao Qing was only curious about Su Hao's strange request, and when Su Hao refused to reveal it, it was inconvenient for him to ask further. As a craftsman, he only needs to make things according to the customer's requirements, and it is inappropriate to ask too many questions. He nodded and said, "What Master Su wants, Xiao Jin can make it, as long as Master tells me the size." However, how many pieces does the master want? ”

Su Hao said: "I'll want a set first, a total of four, two convex and two concave." The convex is three inches, and the concave is one inch and five minutes, what do you think? ”

Hearing the amount Su Hao said, Hao Qing was a little embarrassed: "Master Su, I'm afraid this amount is a bit small, and it's not worth it just to make such four pieces of glass." ”

"Hehe, I forgot about it." Su Hao smiled and patted his head, "It doesn't matter, you just see how many pieces you can make in a pot of glass, I want them all." ”

Hao Qing said: "I use a small crucible, and I can make at least 50 pieces of such glass pieces in one pot." ”

Su Hao said: "Then I'll ask for it all, Brother Hao just needs to say a suitable price." ”

"This ......" Hao Qing looked at his cousin Hao Tong, not knowing how to quote. Hao Tong said: "Big brother, how much money should you charge, just tell Master Su, there is no need to have any taboos." ”

Hao Qing said to Su Hao at this time: "Master Su, I really can't hide it, the colorless translucent glass you want is actually the cheapest one in the glass." However, you have to make a round sheet with uniform thickness and polish, and the material and wage are really not a small number, and Xiaojin can't afford it, so you can only dare to ask Master Su for a price. These 50 pieces of glass, Master Su gave 50 taels, what do you think? ”

"Are you alright, do you think I look like a wronged man?" Su Hao stood up suddenly, staring at Hao Qing with two eyes. He didn't want to play any official prestige, but he really felt that Hao Qing had gone too far, and an ordinary glass lens suddenly offered a high price of 1 tael of silver. What does 1 tael of silver mean in the Ming Dynasty, that is the price of a whole two stones of white rice, and it can be exchanged for a very high-grade Yaowen telescope in later generations.

"Master, the price that Xiao Jin said is already the capital, borrow Xiao Jin's courage, Xiao Jin doesn't dare to ask the master for a price." Hao Qing hurriedly explained, "The raw materials for burning glaze are not produced in our place, and the price is high and rare." Xiao Jin promised to refine a pot of glass for his master, and it would take half a month of work just to make the ingredients, and some materials would not be able to be bought with money. ”

"Wait, you let me think about it......" Su Hao began to realize that something might have gone wrong. He was introduced by the county government, and Hao Tong introduced him, so it was unlikely that Hao Qing would open his mouth to himself. He prescribes 50 lenses for a high price of 50 taels of silver, maybe there is something different in the production process.

It can be seen from the glass bowls made by Hao Qing that the craftsmen of the Ming Dynasty had mastered the craft of firing glass, and were also able to make exquisite utensils out of glass. However, judging from the folk situation, coupled with Su Hao's historical knowledge, it can be known that the use of glass in ancient China was not extensive, so that many people in later generations believed that glass was a foreign product. The reason for this must be that there was a little fork in the glass production process in ancient China, which led to the high production cost of glass and affected its large-scale application in the people.

"Brother Hao, what do you usually use as raw materials for refining glass?" Su Hao asked.

"This ......" Hao Qing stood up, Su Hao's question was too abrupt, in this era, the skills owned by craftsmen have always been kept secret, how can they all shake it out as soon as they enter the house?

When Su Hao saw Hao Qing's appearance and knew that he wanted to keep it secret, he couldn't help but be angry and funny. As a geology expert, Su Hao has found minerals for all walks of life, so he has an understanding of the application of various minerals. He stretched out his hand, crossed his fingers and said to Hao Qing: "Brother Hao, I understand, you want to keep it a secret, right?" I can understand. However, the formula of this glaze, the younger brother has known it for a long time, it is nothing more than quartz sand, soda ash, feldspar and limestone, the younger brother is right, right? ”

"What does the master mean by quartz sand?" Hao Qing asked strangely.

Su Hao thought about it in his mind, vaguely recalled some knowledge about the application of ancient minerals in mineralogy, and replied: "Quartz sand, which is what you call glazed stone, in addition, there is also Fire Qi Bead, which is actually considered this category." ”

Hao Qing said: "It's not strange that the master knows the glazed stone. It's just that this alkaline soil, as well as feldspar, limestone, etc., is not used for small entry. I don't know where the master heard this recipe. ”

"You don't use alkaline earth, what do you use as flux?" Su Hao asked, looking at Hao Qing's confused expression, he knew that he was playing the piano to the cow. He picked up the glass bowl, knocked it in his hand, and suddenly had a thought, scraped it on the wall of the bowl with his fingernails, and then laughed: "I know, Brother Hao, when you refine the glass, you do not use soda ash, you should use ...... Saltpeter, my little brother didn't guess wrong, right? ”

The main component of glass is silica, that is, quartz sand, and it is said that glass is burned with sand, which is not wrong. When smelting quartz sand, some chemical elements need to be added as a flux, and here there are some different options.

When the West entered the glass production, soda ash was used as a flux. The ingredient of soda ash is sodium carbonate, and the glass fired in this way is called sodium-based glass. If limestone, i.e., calcium carbonate, is also included in the raw material, then the glass fired in this way is called soda-lime glass. The most widely used in later generations is this soda-lime glass.

China has discovered the method of firing glass as early as the pre-Qin period, and by the Ming Dynasty, the glass production process was relatively mature, which is why Hao Qing made glass. However, in ancient China, when making glass, lead stone or saltpeter was always used as a flux, the former is called lead-based glass, and the latter is called potassium-based glass, because the main component of saltpeter is potassium nitrate.

The characteristic of potassium-based glass is that the hardness is greater than that of sodium-based glass, and Su Hao scratched Hao Qing's glass bowl with his fingernails, and he could feel the difference in hardness. Glassmakers believed that saltpeter must be used to fire glass, and the production of saltpeter was very limited, which affected the production of glass.

Su Hao has not researched the history of glass manufacturing in China, but he guessed some reasons from the small glass bowl in his hand. Now, he is eighty percent sure that what Hao Qing has mastered is a biased glass formula, and it is precisely because of this formula problem that the cost of glass cannot be reduced.

Listening to Su Hao say another element in the glass formula, Hao Qing began to believe that Su Hao did understand some glass manufacturing techniques. He asked tentatively, "Could it be that Master Su has also refined glass?" According to the recipe you said, can you refine the suitable glass? ”

"Can you get all the ingredients here? Let's follow my recipe and try a pot of glass. Su Hao said confidently.