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- How To Clean and Polish Tiger Eye Stone<\/a><\/strong><\/li>\n\n\n\n
- How To Clean Geodes <\/a><\/strong><\/li>\n<\/ul>\n\n\n\n
A Word About Hardness and Mineral Composition<\/h2>\n\n\n\n
Which approach is viable for an individual stone depends on the chemical makeup of the mineral and its hardness.<\/p>\n\n\n\n
Every rockhound should have a good idea of the Moh\u2019s scale<\/a>. It\u2019s important for most aspects of the hobby. Soft stones don\u2019t do well with harsher methods of mechanical cleaning, even a brass brush can seriously damage a specimen of calcite<\/a> for instance.<\/p>\n\n\n
\n![\"mohs](\"https:\/\/rockseeker.com\/wp-content\/uploads\/2021\/05\/mohs-scale-of-mineral-hardness.jpg\")
<\/figure><\/div>\n\n\nJust make sure you know how hard the stone is. Anything under 5 shouldn\u2019t be cleaned abrasively.<\/p>\n\n\n\n
Chemical cleaning of stones is used to get the best out of specimens.<\/p>\n\n\n\n
It can also lead to ruined specimens.<\/p>\n\n\n\n
For the most part, you can consider silica minerals inert when using chemicals. Very few things will dissolve it, which makes it easy to chemically clean off any minerals that are on the crystals.<\/p>\n\n\n\n
On the other hand, calcium minerals will often dissolve entirely in an acidic situation.<\/p>\n\n\n\n
There are countless other reactions to be aware of. My advice is simple: <\/p>\n\n\n\n
Always do your research on the chemical composition of your specimens before using any chemical cleaning method on them.<\/strong><\/p>\n\n\n\n
Getting Your Hands Dirty: Mechanical Cleaning Methods<\/h2>\n\n\n
\n![\"bucket](\"https:\/\/rockseeker.com\/wp-content\/uploads\/2023\/05\/cleaning-rocks-in-a-bucket-1024x683.png\")
<\/figure><\/div>\n\n\nFor most people, just being able to break off the dirt around a specimen is enough. Stones have a tendency to be harder to clean than you\u2019d think, and it can be frustrating. The following ways of cleaning are a good approach, and most people will use a combination to get their rocks shining.<\/p>\n\n\n\n
First Approach: Soap, Brush, and Water<\/h2>\n\n\n\n
The first thing to try is a scrub brush and a bit of dish soap. You can clean them under running water, but I\u2019ve found that a small bucket is usually the best approach.<\/p>\n\n\n\n
Avoid cleaning stones in your sink. <\/strong>Once or twice may not hurt, but the dirt and sand that comes off your rocks can build up in the pipes. You\u2019ll make your plumber\u2019s day. <\/p>\n\n\n\n
But you\u2019ll be the one with the bill.<\/p>\n\n\n\n
Just get the water a bit sudsy and brush as hard as you can. Use a nylon brush initially, there are very few stones that can be damaged with a normal scrub brush. I like to use a big brush initially and then an old toothbrush to get the smaller spots afterward.<\/p>\n\n\n\n
It\u2019ll get off the majority of the dirt on the exterior of the stone and knock loose any broken bits, but it\u2019s rarely enough.<\/p>\n\n\n\n
Brushing and Probing the Dirt<\/h2>\n\n\n\n
Dental probes are perfect for picking dirt and mud out of the small holes and pockets in a stone. A bit of attention can get dirt that you didn\u2019t even notice on the first pass.<\/p>\n\n\n\n
For very compacted material you can also use a wire brush.<\/p>\n\n\n\n
Stick with brass. Theoretically, steel won\u2019t scratch most silica materials and harder things like corundum. In practice, theory shouldn\u2019t be relied upon.<\/p>\n\n\n\n
Brass brushes shouldn\u2019t be used on very soft mineral specimens, you\u2019ll scratch the surface and possibly do other damage.<\/p>\n\n\n\n
That said, steel brushes aren\u2019t a bad idea for the exterior of stones you\u2019re planning on cutting. A few scratches is no big deal since they\u2019ll be on the edge of the slab and it\u2019s a very expedient method of cleaning deep dirt.<\/p>\n\n\n\n
Consider Ultrasonic Cleaning<\/h3>\n\n\n\n
Ultrasonic cleaners maker short work of dirt, and even some mineral buildup, but you\u2019ll need to be careful using them. They have a bad reputation in some circles, and I\u2019ll cover why in a second.<\/p>\n\n\n\n
Ultrasonic cleaners function by vibrating a container of cleaning solution at a very high rate. This creates cavitation bubbles in the solution which strip out materials. The tiny bubbles can get into even the tightest crevice and remove any contaminants on the stone.<\/p>\n\n\n\n
That same deep cleaning is why they can be problematic for cleaning mineral specimens.<\/p>\n\n\n\n
Ultrasonic cleaners should only be used on hard minerals, and preferably those without any visible fractures on the interior. The cavitation generated in cracks can cause stones to break if you\u2019re unlucky.<\/p>\n\n\n\n
Likewise, porous minerals and organics will break down quickly in an ultrasonic cleaner. The GIA has some good guidelines<\/a> for gemstones that can be applied to mineral specimens.<\/p>\n\n\n\n
Ultrasonic cleaners are the most thorough mechanical cleaning method but they\u2019re also the riskiest.<\/strong><\/p>\n\n\n\n
Sandblasting<\/h3>\n\n\n\n
Sandblasting is best reserved for very hard specimens with a lot of matrix that needs removal. It can affect the surface of most minerals with ease, so you\u2019ll need to do more cleanup before the piece is ready.<\/p>\n\n\n\n
In other cases, it\u2019s a miracle worker.<\/p>\n\n\n\n
Use glass bead as your abrasive media, rather than quartz or garnet<\/a> sand. You\u2019ll do less damage to the exterior, and in many cases, you may avoid doing any damage at all.<\/p>\n\n\n\n
It\u2019s expensive, but if you\u2019re regularly cleaning specimens it\u2019s a great tool to have around.<\/p>\n\n\n\n
Air Scribes<\/h3>\n\n\n\n
For large material removal, it\u2019s hard to beat an air scribe.<\/p>\n\n\n\n
These little tools are sold as marking devices for use on metal. They\u2019re just a tiny pneumatic chisel, and if you have an air compressor they\u2019re inexpensive.<\/p>\n\n\n\n
They should be used carefully. An air scribe is essentially a miniature jackhammer, and a little bit of inattention can do damage to your specimens.<\/p>\n\n\n\n
The use of air scribes is situational, but they\u2019re the best tool to remove large amounts of material to reveal the desired specimen.<\/strong><\/p>\n\n\n\n
Spot Cleaning Guns<\/h3>\n\n\n\n
Spot cleaning guns are used for clothing, but the high-pressure spray of water is great for cleaning up minerals.<\/p>\n\n\n\n
They\u2019re a bit specialized, but not super expensive and they won\u2019t take up a lot of room.<\/p>\n\n\n\n
Use them for the initial cleaning of specimens, they\u2019ll help you figure out what else you need to do to keep the specimen in top shape. In many cases, these may be the only tool you\u2019ll need.<\/p>\n\n\n\n
Chemical Cleaning Methods at Home<\/h2>\n\n\n\n
Before we go any further, I advise you to be very<\/em> cautious when using any sort of chemicals to clean your specimens.<\/p>\n\n\n\n
Some of the chemicals used can cause serious injury if mishandled. If you\u2019re not confident you can use these methods safely then you can give them a pass.<\/p>\n\n\n\n
While some techniques exist for specific minerals, chemical cleaning is mainly used with silica-based minerals like jasper, agate, and quartz varieties. This is because they\u2019re inert as far as most acids are concerned.<\/p>\n\n\n\n
If you\u2019re cleaning things like calcite or flourite, the below will actually destroy your specimen. Always do your research before cleaning a mineral.<\/strong> Even household cleaners can damage some stones.<\/p>\n\n\n\n
First Up: Chemical Safety<\/h3>\n\n\n\n
You\u2019re going to need to have the following on hand to begin:<\/p>\n\n\n\n
- \n
- Safety Goggles-<\/strong>Not glasses, they need to surround your eyes entirely.<\/li>\n\n\n\n
- Rubber Gloves-<\/strong>A small splash can lead to big pain, get a decent fitting pair so you\u2019re not tempted to do anything with them off.<\/li>\n\n\n\n
- Respirator-<\/strong> Even if you\u2019re working outside I recommend using a respirator when working with chemicals like muriatic acid.<\/li>\n<\/ul>\n\n\n\n
Make sure that you have something to neutralize any acids with on hand. A big bag of baking soda is the easiest to acquire. You\u2019ll dump it on any spilled acid to neutralize it before cleaning up.<\/p>\n\n\n\n
Always have safety contingencies in place.<\/strong> A spilled bucket can be a disaster if you\u2019re not ready for it.<\/p>\n\n\n\n
Likewise, you should always perform chemical cleaning outdoors or in a very well-ventilated room.<\/p>\n\n\n\n
While it has some risks, you can do quite a few chemical cleaning techniques at home. Approach with caution, but the end quality of some specimens can be improved by a lot<\/em> if you\u2019re willing to go through with it.<\/p>\n\n\n\n
The Slow Approach-Cutting Calcium Minerals With Vinegar<\/h3>\n\n\n\n
If you\u2019re edgy about using chemicals, you can still use a slower approach to clean off a lot of calcium build-up and other easily removed minerals.<\/p>\n\n\n\n
Cover the specimens in vinegar and allow them to sit for a few days. Most of the time you\u2019ll be cleaning up a quartz crystal or other silica mineral using this method so a brass brush can be used to remove loosed minerals.<\/p>\n\n\n\n
Vinegar can take a few days to work fully. The diluted acetic acid still attacks calcium, but not as much as other acids, the main reason to use it is simply that it\u2019s much safer than most other methods of cleaning.<\/p>\n\n\n\n
Tried and True Calcium Removal With Muriatic Acid<\/h3>\n\n\n\n
Muriatic acid is available as a masonry cleaning chemical, where it shines at removing stains from bricks and concrete.<\/p>\n\n\n\n
It can also rapidly break down less desirable minerals that are included with your specimen. The majority of the time these are calcium-based minerals, often showing unattractive growths on the rest of the crystal. Others might form a deep-pocketed limestone matrix on an agate nodule.<\/p>\n\n\n\n
It\u2019s a simple process:<\/p>\n\n\n\n
- \n
- Clean your specimens of surface dirt and loose matrix with your preferred method.<\/strong><\/li>\n\n\n\n
- Thoroughly dry your crystals or nodules before placing them in a plastic or glass container. Do not use metal containers when working with acids. Pyrex is the preferred material but not required.<\/strong><\/li>\n\n\n\n
- Cover the specimens with muriatic acid, taking care to avoid any fumes or spilling.<\/strong><\/li>\n\n\n\n
- Check on your stones, the calcium minerals will actually dissolve so you don\u2019t need to do anything else to remove them.<\/strong><\/li>\n\n\n\n
- When the specimens look clean, remove them with rubber gloves or tongs and then run them under water from a hose. Take 30 seconds to 1 minute to flush any acids from each sample.<\/strong><\/li>\n\n\n\n
- Prepare a solution of baking soda and water, place the stones in this overnight to neutralize any leftover acids in cracks or seams.<\/strong><\/li>\n<\/ol>\n\n\n\n
Disposing of the acid is easy in most places. Instructions are clear<\/a>, the acid needs to be diluted to 5% or less or completely neutralized before being disposed of down a drain.<\/p>\n\n\n\n
Remember that you always add acid to water, not the other way around. So, if you\u2019re diluting the acid with 10x the volume with water you should add the acid to the water. Doing it the other way around can generate heat and create a dangerous situation.<\/p>\n\n\n\n
You can also add baking soda until the solution stops fizzing. Do this progressively to avoid any problems with heat, but when it\u2019s stopped fizzing the acid is mostly inert and can be disposed of down the drain.<\/p>\n\n\n\n
I recommend going the neutralization route rather than just pure dilution, but both are acceptable under Federal standards. Check state laws if you\u2019re unsure, as some jurisdictions may have more stringent rules.<\/p>\n\n\n\n
Targeting Ferrous Oxide Contamination<\/h3>\n\n\n\n
Finding formations of quartz with a stubborn, orangeish stain is common. In most cases, it\u2019s caused by the formation of rust due to small amounts of iron in the mineral.<\/p>\n\n\n\n
In some specific cases, crystals may have a thin layer of iron oxide formation. This occurs mostly in specific deposits of quartz or amethyst but removing the layer greatly improves the specimen.<\/p>\n\n\n\n
You can use most anti-iron cleaners to attack it. Naval Jelly<\/a> is a favorite, and it works just as well on stones as it does ship bodies.<\/p>\n\n\n\n
It\u2019s not a bad route to go before an acid dip if you\u2019re wary of chemicals.<\/p>","protected":false},"excerpt":{"rendered":"
- Thoroughly dry your crystals or nodules before placing them in a plastic or glass container. Do not use metal containers when working with acids. Pyrex is the preferred material but not required.<\/strong><\/li>\n\n\n\n
- Rubber Gloves-<\/strong>A small splash can lead to big pain, get a decent fitting pair so you\u2019re not tempted to do anything with them off.<\/li>\n\n\n\n
- How To Clean Geodes <\/a><\/strong><\/li>\n<\/ul>\n\n\n\n