Wow, how long would it take for a drop to basically attack down to the bone? Would it carry on and drop out the other side?
What is strange is the more dilute solutions do the worst damage- so you don't actually feel anything until it seeps below the skin hours later. I did read of a case while at GE Semiconductor where it bored a hole through a wrist bone over a period of days. The person ended up in the hospital for quite a long time due to the toxicity of the HF in the body.
Here is a wiki link and it is pretty accurate:
https://en.wikipedia.org/wiki/Hydrofluoric_acid_burnNowadays most of this is handled robotically so less accidents. People don't realize that the production of integrated circuits, solar cells etc. can use some of the most hazardous processes around. I used to work with gases that had a lethal threshold in the parts per million. All this for a Gameboy.