How can one go about finding a very small part lost in the snow? — while working on my motorbike, one of the battery leads fell out and I can't find it. Buying a metal detector for the sake of finding a piece of metal less wide than my pinky finger seems a bit overkill.
Is it magnetic? if so, a big magnet (from a speaker for example) might help...
If the area you lost it in isn't too large, you could shovel the snow into a big bucket, bring it inside, and let it melt. This could be tricky if the area you might have lost it is large, or if the snow is deep. Any other way of melting the snow in place would also work if you have a portable source of heat. If you're in no rush, just wait until spring!
If the site of the tragedy is such that you can easily acquire water, use a hose (or a bucket) and simply run/pour water over the area to melt the snow.
Since snow is an insulator, running a propane torch will be an exercise in patience (and an exercise in buying a bunch of propane). Water is cheap, melts snow faster, and is less likely to burn your house down. Just beware of creating an ice rink on your driveway.
What about salt?
When you add salt, that temperature drops: A 10-percent salt solution freezes at 20 F (-6 C), and a 20-percent solution freezes at 2 F (-16 C). On a roadway, this means that if you sprinkle salt on the ice, you can melt it.
From here.
Apparently you can buy cheap "small crystallized water softener salt", salt for ice & snow melt. You should find it on your local farm store. On a quick search on the internet, I found it for a little over 10 euros for 30 kilos (over 50 pounds) (aquaeuro.com).
Get a Propane Weed Burner Torch (amazon keywords), and follow up with the magnet.
Scan the area with a sensitive compass. Most cellphones have a magnetic sensor also. If the compass direction indicator moves, you may be near a magnetic part. Most steel parts have some magnetism intrinsically there, unless they have been recently degaussed.
The compass trick often works when the material lacks a high enough iron content to be picked up by a magnet, such as stainless steel fasteners.
You might have to move your bike away to scan the area, though.
