KERN & SOHN JE - Manual (Page 4)

Sauter GmbH
Ziegelei 1
D-72336 Balingen
E-Mail: [email protected] Tel: +49-[0]7433- 9933-199
Fax: +49-[0]7433-9933-149
Internet: www.kern-sohn.com
Instruction Manual
JE
JE-BA-e-1211 4
When testing mounted jewellery/ gemstones, they have to
be held with one hand and the tester with the other hand.
When testing a loose gemstone, it has to be placed into a
suitable hole on the metal stone-rest (included in delivery),
preferably on a flat surface. So the stone can’t drop out.
The tester has to be held with one hand. The stone-rest
has to be touched with the index finger of the other hand.
The sensor tip has to be positioned at a right angle to the
gemstone and always at the “table” (top) of it.
For a correct operation, a “circuit” has to be created
between the hand holding the tester and the other one
holding the jewellery or metal stone holder. Therefore the
thumb and forefinger must always be positioned on the
metal panels located on both sides of the tester.
The hands may not be insulated (by wearing gloves) and
the fingers have to be clean.
Also the item being tested may not be insulated (e.g.
costume jewellery set in plastic or metal covered with
lacquer).
8. The readings The red light will appear for another stone (simulant) and
typically gemstones with a higher thermal conductivity,
such as a ruby, sapphire or topaz.
Gemstones with a low thermal conductivity, such as glass
or cubic zirkonia, may not always show a reading on the
Multi tester.
9. Diamond testing (thermal conductivity)
The tip of the tester warms up diamonds (and to a less
extent, rubies and sapphires). Initially, they are “cold”. A
crude test is to touch the stone against your lip or
underside of your wrist to feel this “coldness”. The Multi
Tester measures this “coldness”, e.g. how quickly the heat
from the tip is “drawn” into the stone. Therefore it is most
important that both, the stone and the Multi Tester are at
room temperature. Otherwise, any cold stone (including
any large ruby or sapphire which is “cool”) will register
“diamond”.
Conversely, a warm diamond will register “not diamond”.
Diamonds become warm, being heated by the tip of the
Multi Tester, so when testing the same stone, it has to be
waited two or three minutes between the tests (especially
with small stones) for the stone to cool down. Placing the
stone on a cool surface helps to cool the stone.
10. Moissanite testing (electrical conductivity)
The stone being tested must be absolutely clean. It should
be preferably cleaned with a cotton wool bud soaked in
alcohol. A layer of grease can give a false reading, it is not
sufficient to wipe the stone with a clean cloth.
The Moissanite test is not reliable for stones under 3 points
(note: 72pt= 1inch= 2.54cm), the current can spark onto
the setting of the stone and gives a false reading.
The test tip has to be placed exactly in the centre of the
stone. The sensor and the stone must be seen clearly, in
doubts, a magnifier can be used.
If there isn’t a good close-up eyesight (or an eyeglass) and
a steady hand, there will be difficulties in testing stones
under 10 points.
The reason for holding the tester in the way that the metal
plates are touched with one hand and the setting of the
plate (or metal stone holder) with the other is that the
electrical resistance is measured from the sensor, all the
way through your body and back to the stone. Therefore, if
you are insulated (by wearing gloves) you will get a false
reading. The Moissanite tester is for testing diamond-like
stones, household objects may not be tested.
11. Using the UV light
The quality (wavelength) of the UV light in the Multi Tester
is particularly good for the UV testing.
It will give more accurate readings on Moissanites (UV
light excites the atoms and improves the electrical
conductivity).
-The UV light button has to be pressed to turn it on.