Smash the aluminum oxide and some other waste-like things into powder.
The remaining iron is enough to make a single nail.
After deliberating for a long time, I put the nail on the fire to bake.
Bake it until it's red hot, hammer it especially flat, keep burning it red hot, then use a stone to hammer off two small pieces.
Then tap these two small pieces into the shape of needles.
Still red hot, flatten the end, and drill out the needle eye.
Then quench it with water, take it to a stone for grinding.
He spent countless efforts for these two needles.
Grinding is also a laborious task.
One needle takes an hour, slowly grinding on the stone.
Although it's exhausting, the mood is very good.
This is not a steel needle, but an iron needle.
Not sharp enough.
But at least it's a metal needle.
It's many times sharper than a bone needle.
Moreover, it's very thin.
It looks black, and its shape is neither smooth nor sleek.
At first glance, it's a bit ugly.
