How to Clean Quartz Crystals with Oxalic Acid

You’ve gone on a couple of crystal digs and accumulated a nice collection of Quartz crystals and crystal clusters but you have one problem.  Your crystals have a yellow-brownish stain but you and I know there are crystal clear crystals underneath it.

Here’s a common question I get asked all of the time “How to clean quartz rocks?”

and

How do quartz crystal cleaners work without damaging the crystals?

When your crystal clusters have red clay stuck in between each crystal you’ll need to prep them before you move to the Oxalic acid stage.  The first step is to spray the crystals with medium to high-pressure water.  After knocking off the majority of the clay you’ll want to let it dry in direct sunlight.  Give it 2-3 days and you’ll notice the remaining clay will pull away from the crystals when it completely drys out.

You can do a dry scrub with a soft to medium brush and then spray the crystal with water for a second rinse.

Now you’re ready to move to the method that is used by crystal collecting professionals.  All of us have been using Oxalic Acid to clean crystals for years because it’s the best cleaning solution for removing rust and mud stains from quartz crystals.

Here is a list of items you’ll need before you begin the cleaning process.  Most of these can be found at Home Depot, Lowes, or Amazon.

Tools Needed

  1. 2lb bag of Oxalic Acid (oxalic acid home depot)
  2. 5-gallon plastic container with the lid
  3. Well ventilated area
  4. Glass container if you’re heating the solution
  5. Electric stove top if you’re heating the solution
  6. Think rubber gloves
  7. Metal tongs
  8. Baking soda
  9. Small brush
  10. Medium brush
  11. Power washer

 

Will Oxalic acid damage my Quartz crystals?  We get asked this question often and the answer is no but if you have other types of minerals or organic material attached to the crystal or cluster then those minerals or materials could become compromised. The process of getting these stains off is not an easy one, but knowing the right techniques will help you achieve success. Stains from iron and clay can be quite stubborn but follow the steps below and you’ll have your crystals looking bright white and crystal clear.

 

crystals from twin creek

 

Step by Step Guide on How To Clean Crystals with Oxalic Acid

  1. Remove dirt via high-pressure water and agitation
  2. Your backyard or outside area is best when starting this process
  3. You’ll need a pair of rubber gloves because you don’t want your skin to absorb the Oxalic acid.
  4. A 3-gallon bucket or plastic container (or larger) will be used to contain the water and Oxalic Acid mix.
    1. Pro Tip: Do not use a metal container because the acid will react with it.
  5. Mix 1-pound of Oxalic acid with 3 gallons of water.  If you want a stronger solution then go with 2 gallons per 1-pound of Oxalic acid.
  6. You can pour the entire 1-pound into the container at once.
  7. Stir the mixture for 30 seconds
  8. Place your crystals in the plastic container.  Keep in mind the crystals will displace the liquid cleaning solution.  That’s why it’s best to have a container with room at the top for the displaced liquid.
  9. Place the top or cover on the container and then place it in a warm area.  Direct sunlight is preferred but a hot garage would be a decent alternative.
  10. 3 to 4 days later you’ll want to check on your crystals to see how they’re doing.  More than likely they’re ready to move to the next step.
  11. Take a soft brush and clean the crystals or clusters.
  12. Rinse the crystal or crystal clusters with water.
  13. You can reuse the Oxalic solution for additional cleanings or you can dispose of it.  See below on how to dispose of it properly.

 

crystal points wegner mine

 

How to Clean Quartz Crystal Clusters by Boiling with Oxalic Acid

  1. Remove dirt via high-pressure water and agitation
  2. Your backyard or outside area is best when starting this process
  3. You’ll need a pair of rubber gloves because you don’t want your skin to absorb the Oxalic acid.
  4. A medium-sized glass or ceramic container will be used to contain the water and Oxalic Acid mix.  Please remember to leave room at the top of the container because the crystals will displace the liquid solution.
    1. Pro Tip: Do not use a metal container because the acid will react with it.
  5. Mix 1-pound of Oxalic acid with 3 gallons of water.  If you want a stronger solution then go with 2 gallons per 1-pound of Oxalic acid.
  6. You can pour the entire 1-pound into the container at once.
  7. Stir the mixture for 30 seconds.
  8. Pour the mixture into a smaller glass or ceramic container.
  9. Place your crystals in a glass or ceramic container.  Keep in mind the crystals will displace the liquid cleaning solution.  That’s why you should leave room in the container.
  10. Place the container on top of the portable electric stove and bring the temp up to +/- 200 degrees.
    1. Pro Tip: Do not boil the solution because the fumes will make you sick.
  11. Leave the crystals in the solution for 6-8 hours, depending on how stained or dirty they are.
  12. Check on your crystals every hour or two hours to see how the treatment is working.
  13. Remove the crystals with a pair of tongs or allow the solution to cool so you can remove them by hand, remember to wear rubber gloves.
  14. If the crystals are removed while hot then you’ll want to allow them to cool naturally.  Do not spray them with water, they might crack.
  15. Once cooled, you can spray them with water to remove any stains left over.

 

How to Dispose of Oxalic Acid

Oxalic acid is poisonous and you shouldn’t pour it down your sink or into the sewer because there’s an easier way.  Go to the grocery store and buy a box of baking soda.  Take the baking soda and pour it directly into the Oxalic solution, up to 6 gallons.  Now the solution has been neutralized and you can dispose of it.

 

 

Jerred Morris
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