Our "14-day returns” policy is extended over Christmas. Orders placed between 4 and 19 December can be returned (if not suitable) up to 5 January. Excludes consumables.

Testing acids



Here are 'plain English' precautions regarding the handling of testing acids for precious metals.

If you are a safety officer you may wish to see the COSHH data sheets for gold testing acids.



Burns to skin or clothes should be washed immediately with copious amounts of water and neutralized with bicarbonate of soda; if bicarbonate of soda is not to hand, don't waste time looking for some, just use water.
In the case of contact with eyes wash with plenty of water, preferably under a tap for at least ten minutes, and seek medical advice.

If you think you have a leaking bottle of acid scroll to the bottom of this page.

Please treat the acid with great respect, it is a dangerous chemical, treat it as if it were bleach or ammonia or any other corrosive household product, it will cause great damage if spilt on fabric, it can cause serious injury if splashed in the eye. But please do not over-react, you would not evacuate the house and call out the army if you spilt a bottle of bleach, similarly there is no need to panic if you spill a bottle of acid, just follow the safety precautions. To put the risk into perspective here  are four short 'case histories.' 


Here are five case histories which will, I hope, put the danger into perspective.

The Case of the Stained Hand

A lady called to say, "I spilt the silver fluid, it stained my hand yellow and won’t wash off." She was horrified to learn that the 'yellow stain' was, in fact, a chemical burn and was not going to 'wash off'. But she was relieved, however, to hear that the skin would grow back over the next few days. Had it been the blue acid (that had not been washed off immediately) it may have required hospital treatment.


If you do have an accident with the acid, don't panic, keep calm, wash the acid off under the tap, two or three minutes is long enough for skin, but ten minutes for eyes (and you must seek medical attention if the accident involves eyes). Incidentally, if you wash yourself in icy cold water, the cold will make the skin go completely numb, the feeling will come back when the skin warms.

The Case of the Child

A distraught father telephoned. He had been using the acid and, against all the warnings, had left the cap off, had left it within reach of a three-year-old, then left the room. The child spilt the acid down her leg, the parents did not follow the safety precautions, did not wash the acid off, and the acid had burnt down to the bone. The child needed major surgery and will be scarred for life.


Treat the acid as you would any other household chemical (bleach, ammonia etc): KEEP IT AWAY FROM CHILDREN

The Case of the Sudden Illness

A man telephoned to say he had used the acid, had accidentally sniffed some of the fumes, and a few hours later he felt sick and dizzy. He went to his G.P. who said that it was most unlikely that his symptoms had anything to do with the acid.


Regarding sniffing acid: it is not to be advised, and certainly not on a regular basis, it is not good for the lungs. However, don't worry if you accidentally sniff it just very occasionally, there really is no need to rush to the doctor. Jewellers who have various bottles, old and new, sort them by sniffing the fumes, if it makes them cough and splutter it's a fresh bottle, but this is not to be advised.

However, wholesalers, and some large chains of shops, buy hundreds of bottles at a time – please be very careful with the blue fluid, it always leaks fumes, and whereas the fumes from one bottle will not be noticeable (unless you sniff it) the fumes from hundreds of bottles in an un-ventilated area can be hazardous. Also, if you work with other chemicals that produce fumes, it is possible that the combination of fumes will be harmful. There is no safety data available for the infinite possible number of combinations of chemicals! The best precaution is to work (and to store bottles) in a well-ventilated area.

The Case of the Irritated Eye

A customer telephoned to say that his friend had got some acid in his eye. We asked when this happened and he said a few minutes ago; we asked where the friend was and he said, standing right here; we asked how sore the eye felt and he asked his friend and his friend said quite sore; we gave the official advice which is to hold the eye open under a running tap for at least ten minutes; he asked if he should seek medical advice and (since he had asked) we said yes - we had to assume he had got acid in his eye, we couldn't possibly tell him, "It's probably nothing" when we had no way of knowing.


Please be aware of two extremes. If the person is screaming with pain as their eye dissolves into their brain, do not telephone us for advice, get that eye forced open under a running tap and dial 999. At the other extreme, if you think you may have had some acid on your finger and rubbed your eye but really don't know if you've rubbed acid or dirt (note how black your hands become from handling scrap) - keep calm, the eye 'feeling irritated' does not constitute a major injury, give it a wash and see how you feel in a few minutes.

The Case of the splashed acid

A shop worker testing customers’ jewellery splashed acid over her front and into her face and ended up in hospital with a third degree burn. It seemed improbable to us that such an accident could happen. Then we got to see the security video of the incident. The user was not (as we advise) sitting comfortably at a firm surface with a good light where she could work slowly and carefully. She was standing up, she was in a hurry, she held the item in her left hand, the bottle and the lid/applicator in her right hand, and as she applied the acid she tipped the open bottle upside down over her hand (she wasn’t wearing protective gloves) and over her top. She then panicked and dropped the bottle, which hit the work surface, bounced and splashed acid in her face. She immediately washed the acid off her face (which eventually healed) but didn't remove her top with the acid splash, so that acid remained in contact with her skin (and continued to burn), and by the time she got to hospital she had a third degree burn. In other words, she ignored every bit of safety advice. In this particular case she was using a glass bottle with applicator (the plastic bottles with droppers can only spill one drop). It is to be noted that she was experienced, she had been testing gold for several years.


Even if you are experienced, follow the instructions, sit comfortably, don’t rush, acid is dangerous!


Which bottle is leaking?

Bottles of acid are supplied in sealed plastic tubs. Take the tub to the sink so that you can wash your hands if you get any acid on them (or, better, wear acid-proof gloves - supplied box of 100). Find some tissue (eg kitchen towel, toilet paper, paper tissues) and use them to lift each bottle carefully out of the plastic storage tub. Do this on the draining board and hold each bottle over the sink, take care not to get any of the acid on fabric or furniture. Wipe each bottle dry (the acid will stain the tissue yellow) and place on the draining board. Wait a minute or two then wipe each one again. It should now be obvious as to which bottle is leaking.

If none of the bottles appear to be leaking, wait a few minutes and wipe each bottle again. If, still, none appear to be leaking, examine each carefully by looking at the lid to see if the shrink-cap is white and intact or has turned dark and wet. If all the caps are clean and intact, hold each bottle up to the light to see if they are still full of acid. If all bottles appear to be perfect and are all full with acid, then the probable cause is fumes leaking out of the bottles and condensing on the outside of the bottle (this is certain to happen if you have kept the bottles in the plastic tub, unopened, for several days).

If a bottle is leaking, destroy the acid

Plastic bottles: go to a sink and turn the taps on. Gently squirt the acid into the water that is flowing across the sink. Then rinse the bottle by squeezing it in the water and letting go, so that water is sucked in, then squirting the water out again (do this a few times). Glass bottles: turn the taps on, gently pour the remaining acid into the flowing water, wash out the bottle and cap, taking care not to splash.

Now you need a replacement

Please tell us which bottle has leaked. We can then send you a replacement.


Please return the empty washed-out-clean bottle and cap so that we can carry out our own investigation to find out why it leaked.