In December 1957 Yorkshire UK. Some men found an object which had fallen from the sky
It was metallic circular and Had a strange"script" embossed on its exterior
www.grantham.karoo.net/paul/silpho.html
After a lot of destructive "testing" it disappeared. There were pictures published in a book and an article in the local paper, yet archived copies have them torn out (crude censorship?) as for the article somebody preserved a copy so Its not an Urban legend

As for the disc Someone suggested it was in Scarborough UK into the 60's then it vanished

So Anyone who has relatives in that area or have lived near there since 1957 who has seen this item they are going to open a big news story and It is a Holy Grail Item

Needs to be publicised world wide somebody may have seen it or have an unmutilated book with the picture

For your information the disk was found near the village of Silpho

This article may help locate the item (It's a start?)
www.goddardmultimedia.fsnet.co.uk/tonywedd/saucers.htm

PS
US Government test? Something like that in the 21st century (can believe that Just...) but in the 1950s? Something about the size of a TV set is minuscule then!