
Crystal Pattern Matching Recovers Serial Numbers Obliterated from Metals - ledgeditor
http://www.nist.gov/public_affairs/tech-beat/tb20150218.cfm#ebsd
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sfeng
Acids and etching solutions have been used to do this for many years. It takes
longer, hence the relevance of this discovery, but it does often work long
after the numbers are obliterated visually. My understanding is, similar to
this method, it relies on the structural changes made in the underlying metal
when the upper layers are stamped. It goes to show you just how tricky
materials engineering must be, seeing how the structure of a material can be
so easily changed in an invisible way.

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NoMoreNicksLeft
So keep grinding even after the serial's no longer visible?

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iwwr
Or re-anneal the materials in an oven?

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TrainedMonkey
Putting parts of firearms in the oven, does not sound like a safe thing to do
if you are planning to fire from them afterwards.

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busterarm
But totally the right thing to do with firearms you're trying to dispose of.

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mschuster91
Sounds certainly impressive, but can't this analysis be stopped/manipulated by
simply stamping another serial number or a dot-matrix pattern over the
original serial?

And what happens when the area is heated, e.g. with acetylene, short before
melting point?

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pavel_lishin
It might not help going forward, but I'd wager it'll help close a few cases in
the meanwhile.

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mschuster91
Honestly I don't understand how utterly _stupid_ criminals can be. Especially
guys who _planned_ the crime.

I'd say that being the son of a cop has its advantages in life ;)

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pavel_lishin
I... am not sure what you mean.

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pixl97
$meaning = decode_string("I\'d say that being the son of a cop has its
advantages in life \;\\)" ;

print $meaning;

"They will never find the bodies."

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mschuster91
> "They will never find the bodies."

Heh, if I were on the run for murder the last thing I'd do is post stuff on
the interwebs under real name. Especially not these days, when everyone and
their dog can track each other (hello, SS#7)...

But I'd say the likelihood of me getting robbed or scammed is lower than the
average...

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Retra
That's what someone one the run for murder would want us to think...

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mschuster91
Murder is one of the most stupid crimes to commit - according to Wikipedia,
97.6% of all murder cases are solved.

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sandworm
Are all serial numbers stamped?

I would imagine that some might be cut in. Laser? I presume that such numbers
wouldn't create the changes needed for this technique.

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themoogle
why not change the metal with say a quick spot weld or smack it with a nail
and hammer randomly or small chisel? I wonder if a simple brazing rod would
screw this recovery technique

