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Mizar M24 Electronic Gold Tester
 
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This electronic gold tester accurately and quickly determines gold karat values.

Specifications

• Range: 9, 10, 12, 14, 16, 18, 20, 22, 24 Karat
• Test Times: 2 seconds from 9-14 Karats. 2-15 seconds from 16-24 Karats.
• Delay before beginning test: 12 seconds
• Gold Colours: Yellow, White, Red, Green (see Gold Composition)
• Non-Destructive Testing
• Distinguishes Gold Wash and Flash from Solid Gold
• Can be used to distinguish Gold Plate from Solid Gold (see Testing for Gold Plate)
• Dimensions: Length - 6.3", Width - 4.0", depth - 1.5"
• Weight with Battery - 8.0 oz
• Operating Temperature: 65 - 90 deg F (19-32 deg C)
• Battery: one standard 9 volt
• 2 year warranty

• M24 Electronic Gold Tester
• Eraser
• Testing Solution (No. 1995)
• Owners' Manual
• Eraser Pencil

Operating Instructions

1.  Testing for Gold from 20K to 24K

When testing gold from 9-18K, go directly to instructions below. When testing gold from 20-24K, a buildup of test solution on the Reference Gold will have to be removed to obtain the proper results.

Step A - Sharpen the Pencil Eraser and cut off the end with a sharp knife or razor so that it is flat and round. Then place the eraser into the Test Well and firmly rotate back and forth for about four seconds. Brush debris from the Test Well. This prepartation will eliminate the excess buildup on the Reference Gold.  For all tests of 20-24K gold, do this step of removing excess buildup on the Reference Gold with the sharpened and blade-cut Pencil Eraser. A dirty Eraser tip will not sufficiently clean the Test Well.

Step B - Go to Item 1 below.

2.  Testing Gold from 9K to 18K

Item 1 - Thoroughly clean immersible area of Test Gold with the Gray Eraser (see Do's and Don'ts). Attach Alligator Clip to Test Gold away from immersilbe area.

Item 2 - Loosen the cap of the Test Solution and have a soft paper towel and some Q-Tips handy.

Item 3 - Press Test Yellow Gold or Test White Gold (to match the type of gold that you are testing) and within two seconds, put three or more drops of Test Solution into the Test Well. Quickly squeeze all the air out of the Test Solution Bottle and tighten cap firmly (see Item 6).

Item 4 - Observe that one of the Karat Value Lights is on. Any Karat Light may be lit; this is determined by a previous test or length of time that the unit has been off. After the Light goes out (within one second), carefully immerse enough of the Test Gold into the liquid to start the Testing light, being careful not to touch the reference Gold at the bottom of the Test Well and being careful not to touch the Alligator Clip to the liquid. Hold the Test Gold without moving it until Testing Light goes off. This will take 2 to 15 seconds depending on the Karat value of the Test Gold. User should brace the heal of his/her hand on the unit or on the same surface as the unit rests on. When possible, brace the Test Gold on the inside of the Test Well just under the sufrace of the liquid and be very careful not to touch the Reference Gold at the bottom of the Test Well. It is important that the Test Gold not be moved about in the Test Solution until a reading is obtained.

Item 5 - When Testing Light goes out, remove Test Gold. Read LED Display of Karat Value. Clean Test Gold thoroughly with soft paper towel. Thoroughly wipe the Test Solutin from the Test Well using a paper towel followed by a Q-Tip. If re-testing is desired, see DO'S and DON'TS.

Item 6 - Check to be sure that there is not excessive air in the bottle and that the cap is tightened firmly.

Precautions

• After testing Gold item, it should be cleaned with a buffing wheel. Regardless, it must be cleaned with the grey eraser before any new test because of the residue left on the Gold from the previous test.
• Improper or insufficent cleaning of the Test Gold before testing can increase the Karate value readings.
• The unit is operating corrctly if occasionally you do get a reading in the next range. This can happen when the karat value of the Gold you are testing is very close to the odd karat value (eg. 17K, 19K). Your unit is operating correctly when this occurs and indicates the gold you are testing is very near the in-between value.
• The excess air must be squeezed out of the test solution bottle between tests or when stored. Squeezing out the excess air keeps the solution fresh. When all of the air cannot be queezed out it needs to be replaced. In any case, the bottle must be replaced 6 months after first opening! Un-fresh test solution can cause the karat readings to go lower by one range. You should always have a fresh bottle of Test Solution available.

• Don't use Testing Solution for more than one test - errors will result.
• Don't touch Test Gold or Alligator Clip lead to Reference Gold at Bottom of Test Well. If this happens remove liquid and re-do test procedure.
• Don't let Alligator Clip touch liquid.
• Don't leave liquid in test well. This will void your warranty.
• Do clean Test Gold before testing if it isn't bright and shiny. Unclean Gold may result in inaccurate readings.
• Do keep Gold chains very tight (link to link) during testing. Use the fewest number of links (one if possible) between the Alligator Clip lead and the Gold link to be immersed in to the liquid. Three problems can exist with testing chains:
• There may be dirt or contamination between links that would require intensive cleaning (ie. ultrasonic) before testing.
• Some chains, especially certain European manufactured chains have a thin non-metallic coating that must be removed from an area before testing. The eraser pencil may be used to remove this coating.
• When testing chains, remember that the solder often used at the link(s) is of a lower karat than the rest of the chain. Therefore avoid testing in that area.
• Do make sure good contact is achieved between the Test Gold and the Alligator Clip lead. If the object to be tested is too large to fit in the clip lead, simply hold the clip lead lightly against the Test Gold during test.
• Do always clean the Test Gold with the Gray Eraser before retesting in the same location. Pink eraser can be used but it requires considerably more pressure and effort for accurate readings.
• Do replace the Testing Solutions every 6 months after opening.
• Do use only within Operating Temperature 65-90 deg F.

• In the event the Alligator Clip contacts the testing solution, the Alligator Clip must be rinsed thoroughly with water and dried before using again.
• Warning: Eye Hazard - Read warning label on bottle of Test Solution.
• Important: The Testing Solution is sensitive to exposure to air. Minimize the time cap is loose on bottle.

Introduction

Probably most of the gold plated items referrd to as costume jewellery or fashion jewellery contain gold at the surface which is no thicker than 8 millionths of an inch. Such gold plate is referred to as Gold flash. A large percentage of Gold flash is sufficiently thin and/or porous (microscopically) that the M24 Gold Tester will read through the plate and indicate Not Gold. A thicker plate will read karat Gold unless a portion of the surface being tested is erased with the eraser pencil or filed to expose the metal underneath. The eraser should be used as first choice since it is easier to use and is non-distructive; however; the erase will not work on thick Gold plate.

General Description of Procedure

To determine that an item is Gold plated non-Gold, the user of the M24 must take at least two different readings, including one reading of a surface which has not been erased or filed. The reading of the erased or filed surface will be lower if the metal underneath is not Gold. (To be sure the metal underneath is not Palladium, see the section on Testing for Palladium). The M24 Gold Tester will read as Not Gold if a sufficient area of non-gold is exposed to the liquid but the un-erased or un-filed gold plate exposed to the liquid does have some effect on the reading. This is why the following Precautions are important.

When testing for heavy Gold plate, it may be necessary to use a fast drying lacquer or material such as a clear fingernail polish. The area to be tested must be coasted with the lacquer and allowed to dry. Next, make a file mark in the center of the coating deep enought to expose the base metal. Then test the exposed base betal with the M24 Gold Tester. Do not allow the Testing Solution to touch any part of the Gold that has not been coated.

Precautions

• When testing the un-erased or un-filed portion, be sure that the test area has been relatively unaffected by wear. Flat or thin Gold plated items will tend to be worn at the edges. If it is difficult not to expose a worn area when testing an un-erased or un-filed area, the user may wish to selectively mask any area in queastion with fast drying lacquer. The reason for masking a worn surface is that if you test a worn surface first you may obtain the lower karat reading before any erasing or filing has been accomplished. You therefore, may not get a lower Karat value on your second test and not be able to determine that you are testing Gold plate.
• When testing the erased or filed portion, be sure that enough of the surface area immersed in the liquid is erased or filed down to expose the suspected base metal underneath.

The vast majority of Gold plate is 22K or better. Most Gold plated jewellery is flash Gold plate and most flash Gold plate is less that 5 millions of an inch (1/8 micron). The M24 Gold Tester will read right through the 22K Gold plate and indicate anywhere from not Gold to 12K Gold. Anytime you get a 12K or lower reading, Gold plating should be suspected. To determine Gold plate simply use the grey eraser on the test site and then inspect for the presence of base metal.

Inspect the Gold colour of items reading 9-12K gold. If they are really 9-12K, they would not have that rich colour of a 22K gold plated item.

Final Point
It is strongly recommended that users of the M24 Gold Tester practice testing for Gold plate on a few items believed or known to be gold plated. A few sets of practice runs dscribed under General Description of Procedure will impart confidence to the point that the user will find testing for gold plate to be fast and easy.

Gold Composition

There are four basic colours of Gold:

Yellow - most common
White - second most common
Red (Pink/Rose) - uncommon
Green - very uncommon

The M24 Gold Tester can distinguish between Karats of the two popular colours, Yellow and White, by means of colour selector buttons.

• Most red colour gold can be determined by using the White range selector button.
• Most green colour gold can be determined by using the Yellow range selector button.
• There are no ranges that are compatible for use on dental gold alloys.

4.  Testing for Platinum
Platinum is indicated when the test-item reads 22k or higher using the White Gold range selector button. This is because white gold above 18K is virtually non-existant.

5. Testing for Palladium
Both Palladium and Platinum will indicate Karat Gold if tested. Platinum jewellery is usually traded at a higher price than Gold jewellery, so Platinum is seldom marked as Gold. Palladium, however, is one-quarter to one-third the price of pure Gold, so it should be noted that pure Palladium may read as medium Karat Gold. Paladium prong settings are sometimes soldered into diamond solitare White Gold rings. If Palladium is suspected, it is easily distingished from Gold as nitric acid will quickly turn Palladium dark - Gold is not affected in this way.

Maintenance of the M24
No maintenance is required.

Battery Replacement
When the Low Battery indicator flashes, it is necessary to replace the battery before operating the unit. Simply remove the 4 small screws located under the rubber feet on the rear of the Gold Tester. Carefully remove the rear cover. Locate the 9 Volt Battery and replace with a new one. Replace the rear cover, being careful not to pinch the wire leads with the cover. Replace the 4 rubber feet.

Trouble Shooting Guide

Problem
Yellow Gold or White Gold light does not light.
Low battery light is flashing.

Cause/Solution
Replace Battery.

Cause/Solution
Clean test Gold in area to be tested.
Alligator clip not connected to test Gold.
Reference Gold coated. See note at end of document.

Cause/Solution
Test Gold removed before testing light goes out.
Test Gold or clip being shorted to Reference Gold at bottom of Well.

Cause/Solution
Temperature not within 65 - 90 deg F.

Cause/Solution
Alligator clip in liquid during test.

Warranty
RS Mizar provides that each M24 Gold Tester System will be free from defects in material and workmanship for a period of 2 years from the date of purchase. This warranty becomes void by:

• Unauthorized repair, misuse, modification, alteration, tampering or breaking any factory seal.
• Accidental damage, neglect or improper use.
• Leaving Testing Solution in Test Well

RS Mizar and Lacy West Supplies shall not be held legally liable or responsible for any error in determing the gold content of any object using the M24 Gold Tester.