Hi

I recently bought a Busch Diamond 8203 Hss Twisted Drill 1.5mm bit, after a recommendation, to go into my Dremel 3000 to drill sea glass. I used it for the first time yesterday, and I was very pleased when I started to drill some small pieces. But after drilling 5 pieces it stopped actually making any headway into the glass, making only a small indentation. I tried a few pieces thinking the first one it stopped working on might have been a bit hard, but it was the same with the other pieces, hardly a mark on the drill spot. I tried again this morning, and again it wasn't drilling a hole(?)

How long should such a drill bit last?

Thanks