Most of your finds will come out of the ground covered in sand and dirt, perhaps even stained with iron however Azurite & Malachite are very fragile and will slowly erode even with a delicate touch. Follow the instructions below to clean them safely.

These instructions focus on azurite rosettes, blueberries and similar structures as well as malachite specimens. These minerals have a Mohs hardness of about 3.5 to 4 and therefore require a delicate touch. Aggressive physical cleaning should be kept to a minimum to avoid damaging the finds.

Before any heavy cleaning, give your pieces a simple rinse to remove loose dirt and mud; treat your prize finds with care. Soak in water overnight, clean and rinse thoroughly, dry completely and look them over. After this step some of your finds may be clean and ready to go.

After rinsing your finds, depending on what you find, follow the steps below to continue cleaning your pieces. There is no specific cleaning order. Typically you should start by removing any biological coatings, then hard clay & dirt coatings before moving onto any harder deposits. Keep in mind the more time you spend cleaning, the more you increase the chance of damaging your finds. Do as much effective cleaning as possible in as short amount of time as you can.

TOOLS

BIOLOGICAL COATINGS

CLAY & DIRT

IRON STAINING

WORKING WITH ACIDS

TOOLS

Check yourself before you wreck yourself.

The more tools the better but here is a list of what you will need at minimum to effectively clean.

  • Sieve, Tight Mesh
  • Brushes; Toothbrushes, Nail Brushes, Nylon Cleaning Brushes
  • Dental Picks
  • Bamboo Skewers & Toothpicks
  • Ultrasonic Cleaner
  • Textile Spot Cleaning Gun
  • Buckets
  • Safety Glasses
  • Rubber Safety Gloves

Chemicals & Acids

  • Distilled Water
  • Chlorine/Bleach
  • Acetic Acid/Vinegar

BIOLOGICAL COATINGS

A simple soaking overnight in bleach will loosen and remove most biological coatings like moss and lichen. Use brushes and wooden tools for persistent stains.

Rinse and soak with clean tap water for 24 hours and then dry completely.

Tough to remove items like roots and other debris may be cleared with more aggressive techniques but be careful.

SAND, CLAY & DIRT

For pieces that are heavily coated with sand and dirt start with a good rinsing under water in a sieve. Follow with a thorough cleaning in an ultrasonic cleaner. Most of the loose dirt will be cleaned in his process. In the case of stubborn dirt, dry the specimen to loosen the dirt and then treat in the ultrasonic cleaner again. This process can be repeated however each session will slowly degrade the specimens.

Deep Set Non-Mineral Coatings

If deep set dirt and debris remain after cleaning with manual means; it is time to move up to a more aggressive technique to remove stubborn deposits. Using a Waterpik or Textile Spot Cleaning Gun is ideal for this however you do risk damaging specimens if used to aggressively. Due to the delicate nature of Azurite and Malachite use with extreme caution to remove deep set dirt and other deposits from your pieces and let dry, respray if needed. Any deposits remaining at this point call for direct mechanical removal.

TEXTILE SPOT CLEANING GUN

This is our favorite tool! It is powerful but non-destructive … mostly. It is strong enough it will break a fragile crystal so start with a junker and leave your prize finds until the end.

This device emits a high powered jet of water capable of forcing water under the skin. Use extreme care with this device. If you are using on specimens that have been in a chemical and/or acid bath, remediate the chemical before using this tool; ‘airborne muratic acid’ sounds like a 2020 headline.

Like all tools, start easy and increase pressure to remove stubborn deposits of any kind. Small flaws that look microscopic can be cracked. Be careful on combos, clusters, and plates; tenuously attached finds can be broken with this tool.

The textile gun is traditionally used in the textile printing industries to remove stains and ink overprinting from silk screening. It works wonders for cleaning specimens of any kind as long as they can handle aggressive treatment. Additionally, there is a lot of spray back as you use this so the warning to use safety glasses can not be stressed enough.

Author’s Note: I spent the afternoon with an ophthalmologist to find I had an abrasion on my cornea from spray back using a textile gun.

TEXTILE SPOT CLEANING GUN CARE

The textile spot cleaning gun is not intended for use with water unfortunately, it is meant for use with dry cleaning solution. It will work for a period of time and then the mechanism eventually freezes up. The best protection against this is to fully blow out all the water after every session and oil frequently.

IRON STAINING

Removing iron staining can prove to be a difficult challenge. Chemical cleaning with traditional rust removers will ruin your specimens; leaving them covered in a black stain. It is advisable to try physical removal using lightly abrasive techniques such as toothbrushes, skewers, dental picks, waterpik, and textile spot cleaning gun.

If you do choose to try chemical removers and end up with stained specimens, soak them in vinegar (acetic acid) until the stain is removed but use cautiously as vinegar will slowly dissolve the specimen.

FINISHING

After all the dirt and deposits have been removed give your pieces a final examination. If you are satisfied they are ready for display. Exercise caution displaying specimens that are UV reactive or that will fade in direct sunlight. When your pieces get dirty from display over time take a quick pass under water in a sieve and dry.

Any questions let us know and remember, start with a junker!

ACIDS

Many of the cleaning methods mentioned on this site use chemicals. Be sure to review this section on the proper use of acids and chemicals and the manufacturer directions provided with the chemicals you purchase.

ADHERE TO THE FOLLOWING PRECAUTIONS WHEN USING ANY ACID

  • Use glasses and rubber gloves to protect your skin and eyes.
  • Mix the acid with distilled water; always add acid to water and not water to acid.
  • Work in small controllable batches.
  • Do not overload your solution.
  • There will be evaporation as you go so anticipate volume loss.
  • Lower your specimens into the solution slowly with a slotted spoon or tongs.
  • Have neutralizing agent on hand such as baking soda or agricultural lime for acid spills and vinegar for alkali spills.
  • Have plenty of water to clean up spills and to rinse and soak your finds after the chemical treatment.
  • Work only in a well ventilated area.
  • Work only in a well lit area.
  • Adhere to all manufacturers warnings for any chemical you use.

HEATING ACIDS

Heating acids will increase their effectiveness however the fumes created are dangerous. To try this method use an old crockpot with a plastic lid in an outdoor or ventilated area.
DO NOT TRY THIS WITHOUT A FULL RESPIRATOR.
DO NOT DO THIS ON THE STOVE IN YOUR KITCHEN.
DO NOT DO THIS WITH MURATIC ACID – IMHO

NOTE ON ACIDS & CHEMICALS WITH MATRIX AND HOST ROCK

To avoid absorbing chemicals and acids into porous host matrix, soak specimens in distilled water for 24 hours prior to chemical or acid exposure.

Drying between different steps is needed to get a good review of your cleaning progress but be sure to soak again prior to the next phase of chemical cleaning.