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Name: Steve
Status: other
Grade: other
Location: KY
Country: USA
Date: Summer 2010

I was using a metal detector and found a piece of what looks like cobalt colored glass....but it is Extremely Magnetic. It is also Extremely Dense. I have worked in aerospace and defense field for 14 years. I even worked on the Stealth Bomber when it was a Top Secret Project. I have worked with all types of exotic metals...some, I cannot even mention....but I can not identify this piece. It is a odd shape (not part of a tool or piece of equipment) very shiny cobalt colored and has a slick glass like appearance; about 1 1/2 inches with no flat sides or ends semi cone shaped...honestly, it does not look like anything I have ever seen from this world. This tiny piece is so magnetized that it can pick up a full sized music stand. It is hard and as slick as glass. What could it possibly be?


I would start with trying to be a bit more quantitative - "extremely dense" and "extremely magnetic" are not sufficient. Since you appear to have some fairly technical background, I'm dispensing with some of the basics. There are lots of rare-earth ceramic magnets out these days. They are remarkably strong compared with what was available even just a few years ago. You can disperse magnetic powders in a lot of different materials too, even blue glass. I would start by measuring the field strength with a gauss meter and determine if it is within normal ranges for a rare earth magnet. Specs are published online in many places. You can also measure its bulk density and compare to known materials. If it falls outside the ranges of known materials, you have one set of possibilities, and if it is inside the range, then another set.

If you have access to the tools, you could XPS it to get an atomic composition. You can cleave it to get internal readings. There are a ton of qualitative analytical tests (chemical tests too) to identify an unknown.

Or, just take it to a nearby materials science department and see if a kind professor can help you. They might look at it and identify it by sight.

Hope this helps,
Burr Zimmerman

Where did you find it?

Could it possibly be cobalt sea glass that people find washed up on beaches? sea-glass-of-puerto-rico/sea-glass-colors.html

from this URL:

Sea glass, also known as beach glass or mermaid's tears, is nature's answer to bottles, china and pottery carelessly thrown into the sea many years ago. The glass is tumbled on the ocean floor, smoothed by the waves and sand until it washes up on shore, waiting to be found by a lucky passerby.

I do not know how magnetism fits in.

If this is a significant puzzle for you maybe you can find someone to do spectroscopic work for you. Here is one possible service for you:

Sincere regards,
Mike Stewart

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