Unknown ordinance found in stream? (photos included)

I was walking in a remote area in south-east England and I found something unusual in a stream.

It is about 8 inches (20cm) long, has/had a white stony casing and inside was a metal thing with a grenade/pineapple design exterior.

Is this a WW1/WW2 era device or just some random metal garbage?

93914709_3014256018613220_9174711715248472064_n by Steve Chipman posted Apr 17, 2020 at 9:08 PM

93140135_2303286849965171_7561439015807746048_n by Steve Chipman posted Apr 17, 2020 at 9:08 PM

93478722_862277724182778_2192248292534910976_n by Steve Chipman posted Apr 17, 2020 at 9:08 PM

 

It looks like a rifle grenade. I would leave it well alone and call the police who will alert the bomb squad who will make it safe.

 

I would concur. Looks like a 1917 Hales No 20 Mk I rifle grenade. The fact that it has a thin layer of cement or concrete around it might have been an attempt to increase fragmentation in which case it could be part of an improvised mine or booby trap made by the Home Guard or Auxiliary Patrol in 1940/41. Definitely leave well alone and notify.

 

And to all who may partake, or contemplate partaking, in magnet fishing my advice would be don't. No good will come of it.

Best intentions and kind regards, always,

Jim.

 

Particularly the No 3 and No 20 rifle grenades which were percussion detonated.

 

Update: I called the police, and the bomb disposal team came.
Apparently, it was just a big lump of tar. It was cracked open and it just crumbled away.

Sorry for the anti-climax

Thanks to everyone for their help anyway.

 

Better safe than dead - possibly the mot juste for the current situation