You would think that putting a magnet on a marble would be pretty straightforward. I had no idea how complicated it could get.
My first goal was to make a quality product. I like strong magnets so I made sure to get Neodynium, also called Rare Earth magnets. These are the strongest magnets. What I didn't realize, and I don't know why it's common sense, is that the tiny magnets would have a tiny pull.
The tiny magnets looked very cute on my marbles. However, they don't have the strength that I prefer. I put them on my refrigerator and they can hold up one paper. When I took it to work I felt it didn't hold up the things I needed them to. I was very disappointed with the quality and have now taken these particular magnet I had to take out of my store.
I am now using magnets with a 6lb pull strength. Yes, now I'm learning all about the different magnets and how they measure strength.
I have also learned more about glues. I found Gorilla and Loctite glues don't work for what I need. I am happy with e-6000 glue, although I will continue to experiment.