Testing $200 gold koala Sigma Investor

[SULLA]

Set to 22k.
Correct Weight set.
Coins weighs correctly on scales.
Diameter is correct with calipers.

Fails on Sigma investor.

Full soverigns verify correctly.

What am i doing wrong?

Anyone know how to fix?

XRF SCANS CORRECTLY.

 

[betterinvestmentthanshare]

You verified via wand or straight on the sigma?
Repeat test at least 3 x turning sigma off and on before each test.
Did you try both sides of coin?
Calibration reset?
Surface clean on sigma and coin, no oil from fingers?
Do you have a different 22ct coin to test?
Is the sigma stored in a cool, dry environment?
Process of illumination

 

[SULLA]

Thank you BITS, but the coins are in exceptional clean (unc) condition. One in capsule and the other still sealed in original packaging.

Used all wands and lnvestor onboard sensor and all variations of 22k (Au+Ag and Au+Cu).

Tested Full Sovereigns without issues.

Will try the on/off suggestions.

 

[betterinvestmentthanshare]

I’ve had 2 negative results on 1/10’s in capsules. Took them out to test and results were positive

 

[SULLA]

Tried the on/off scenario with same result.