This is the fictional formula (Nital) that depetrifies stoned people and stoned birds in the Z=1 Stone World. chapter 1 p30

Senku puts a pail for the Nitric Acid dripping near the spot where he and Taiju depetrified. chapter 2 p6-8 He tries the Nitric Acid on the stoned birds but it did not work. chapter 2 p10 Then Taiju hints about sake using grapes and made the wine. chapter 2 p12-16

They continued making Brandy. chapter 2 p17 And they later found the stone formula. chapter 2 p20-22

IMAGE Senku thought about something chapter 2 p13

Senku tried the stone formula on other statues. chapter 3 p3

Mixing the stone formula. chapter 5 p7

Senku hypothesizes the formula need not only Nitric Acid, but bat urine as well. chapter 5 p12

They squirt the concoction onto her face and the Stone Formula heals her. chapter 7 p12