Ari synthetic-diamond tester by Presidium

Summary The Presidium ARI is an essential tool for the experienced jeweller and professional diamond dealer, it is for testing known diamonds, to see if they are natural or synthetic.    If you are not an experienced jeweller or professional diamond dealer: check with a simple (but good quality) diamond tester to make sure you have a diamond or Moissanite (you won't know which) then use the ARI to see which (diamond or Moissanite) it might be and if it's diamond the ARI will tell you the chances of it being a natural diamond or a synthetic diamond.  Warning: as the batteries start to get low, this tester give incorrect readings. Instruction manual (pdf download) Videos (youtube) Guide to buying diamond testers (web page) Video Detail Natural diamonds grow as crystals deep in the Earth, they are brought nearer the surface through volcanic activity where they are mined (they are also known as as mined diamonds).  It takes 2 to 3 billion years for a diamond crystal to grown naturally.  Synthetic diamonds are grown by man in a laboratory over a period of a few weeks. "Synthetic" is the scientific term. Colloquially, we say lab-grown or manmade or lab-created.  It takes a few weeks grow a synthetic diamond in a laboratory.  Synthetics and naturals are identical, they are both diamond. They are the same chemically, they are the same optically. That is why it is so difficult to tell them apart. If you just want to know if you have a diamond or not a diamond, see our Guide to buying diamond testers.   GUARANTEE 1 year Features comfortably handheld  can test any stone mounted in jewellery (in addition to loose stones) also tests for Moissanite  fast response time (test-result in 3 seconds) left-handed or right-handed use one year guarantee INCLUDED The tester Neat heavy-duty carrying pouch USB power cable (for use instead of batteries) Spare test-tip Calibration disc Stone-holder for loose stones (you can also test stones mounted in jewellery) Polishing cloth (to clean the stone before the test) Alcohol wipes (for cleaning the test-tip) Operation 1) Clean the top (table) of the stone thoroughly with the polishing cloth 2) Insert the probe into the tester 3) Do not remove the cap. Turn it on, wait 10 seconds for it to warm up 4) Remove cap, hold probe on the black disc supplied and wait while it calibrates 5) Place the probe in the centre of the stone as instructed on the display and see the reading (details below). 6) When you have finished all your testing, remove the probe from the tester and put it safely away in its case. THE READINGS: CVD / HPHT / Type IIa diamond CVD/ HPHT are two are methods of growing diamond = synthetic Type IIa diamond is a very rare type of natural diamond that will show up as 'synthetic' on this tester. So if the tester shows, "CVD / HPHT / Type IIa Diamond" there is a good chance it's synthetic but this is not guaranteed. DIAMOND By "diamond" they mean natural diamond.  MOISSANITE Moissanite is not diamond (neither natural diamond nor synthetic diamond) but it is useful to be able to detect these because they show up as diamond on cheap diamond testers.  You notice that there isn't a reading not diamond ("simulant"); if you are not a diamond dealer or experienced jeweller you must be certain you are testing a stone that will register 'diamond' on most diamond testers; testing non-diamonds on a Synthetic Diamond Tester can give incorrect readings. Technical Size 190mm X 46mm (1.2 inches) X 25mm  Weight 60g  Tests* stones from 0.02 to 10 carats incl. mounted stones in any setting Tests* stones of colour D to J Tests* round (brilliant-cut) stones that are perfectly polished * It is important to understand what these limitations mean, see our guide to synthetic-diamond testing. RESPONSE TIME Start-up time 10 seconds Testing time 3 seconds POWER Power: three AAA batteries (supplied) or any USB power source (USB cable supplied) Battery life: 4 hours of testing Auto-power-off yes, if used on battery power it turns itself off after 10mns of non-activity. ACCURACY Gives correct results about 95% of the time (6% false positive rate, 4.5% false negative rate) providing the colour is 'clear' (colour D to J) and the size is at least 0.02ct and the cut isn't shallow. GUARANTEE 1 year Limitations, please read! The Presidium ARI is not for testing diamond v. non-diamond. It is for showing you the chance of a diamond being natural (originating from the earth) or synthetic (manmade in a laboratory) - both are 'real' diamond. The ARI also distinguishes diamond from Moissanite.  A synthetic-diamond tester is for the experienced jeweller and professional diamond dealer.  5% of natural diamonds have an unusual composition ("Type IIa diamond") and cannot be distinguished from synthetic diamonds.  Stones must be at least 1.3mm diameter (approx. 0.02ct) so if the stone is small, check it with a diamond gauge. For the non-expert: