Plenty of youtube videos of a blade-off test - here's a short one [0] of an A380 Rolls Royce engine testing. That's about £9,000,000 of engine being destroyed in this (successful) test.
At the beginning of the video the blades seem to be spinning at about 2RPS, but after the explosion they're spinning much faster. I presume the former was an artifact of the camera's frame rate.
They normally have high-speed cameras running; that short video is a mish-mash of super-slow-mo and regular speed footage. There are much longer versions on YT, e.g. this one [0] which covers it in more detail (watch the people in the room jump when it blows - despite being a fair distance away).
[0] https://www.youtube.com/watch?v=5-8_Gnbp2JA