Panning for Gold

When I felt like my vision was off while working, I realized I had lost one of my contact lenses. This was shortly after I had become the store manager.
I was clearing the dishes in place of a part-timer who was on break, and although I searched around my feet, I couldn't find it. It seemed I had dropped it into the sink. The sink was filled with water, and dirty dishes were soaking in it. The water was stained the color of meat sauce, with oil floating on top.
"Ugh, I dropped my contact lens."
Just then, Ueda-kun, a part-timer, came back, so I grumbled to him.
"Seriously? Isn't it dropped around there?"
"I looked, but it's not there. I think I dropped it in the sink."
"Oh no."
When I said it couldn't be helped, Ueda-kun said something that sounded like a famous quote: "It's definitely in there. It's game over if you give up now," and started scooping through the dirty water with a colander. He then squinted to check the leftover food he had scooped up. It was just like panning for gold at the bottom of a river.
"It's definitely in there."
I was very grateful for the sentiment, but I didn't want to put something that had come out of such dirty water into my eye.
"Thanks. But it's okay now."
"But, it's definitely in there."
Ueda-kun wouldn't stop his gold panning. It seemed he was actually enjoying the task of searching.
In the end, he continued searching the bottom of the dirty water while washing dishes, and finally found it before closing time.
"Manager, I found it!"
"...Thank you very much..."
"Glad you didn't give up, right? They're expensive to buy."
"...Yeah..."
I was grateful he found it, but I still couldn't bring myself to use it. I secretly threw it away.