Buzz
Paua, also referred to as “abalone” in the U.S. and Australia and “ormer” in the U.K., encompasses various species of large, edible sea snails. While traditionally considered a culinary delight in coastal areas, it also captivates collectors with its stunning iridescent shell, displaying shades of red, gold, and blue-green when properly polished.
Instructions
Sanitizing Paua Shells with Bleach
Create a diluted bleach solution in a sizable container. Fill a bucket or similar vessel with 3–5 gallons (11–19 L) of clean water, then add approximately 1–2 cups (240–470 mL) of bleach. This concoction forms a gentle soaking mixture effective at eliminating bacteria from paua shells without causing deterioration or damage.
Soak your paua in the bleach solution for at least 30 minutes. For optimal outcomes, leave them immersed for several hours or overnight. As they soak, the bleach will gradually sterilize the shells, while also loosening stubborn dirt, enhancing their vibrant colors, and eliminating any unpleasant odors.
- Ensure the shells are fully submerged. Adjust the water and bleach quantities as needed based on container size and the number of paua being cleaned.
Alternative: If you're concerned about bleach affecting your paua's colors, fill the container with tap water and soak the shells for up to a week. Follow this with a brief boiling to eradicate any remaining germs.
Clean the bleached shells with warm, soapy water. After soaking for your desired duration, remove the paua from the solution and take them to a sink. Rinse each shell under running water to eliminate excess bleach, then swish them in a container of warm water and mild dish soap.
- Wear gloves when handling the shells. Using metal tongs is another option to minimize risk.
- Rinse the shells thoroughly after the soapy bath to prevent a cloudy film from forming.
Allow the shells to air-dry. Choose a well-ventilated area indoors or nearby. Lay out an absorbent towel and arrange the paua on it with their outer surfaces facing up, leaving space between each shell. They should dry completely within a few hours.
- Drying outdoors is acceptable but avoid direct sunlight, which can fade their colors.
Using Muriatic Acid for Shell Cleaning
Ensure your safety with a facemask or respirator, gloves, and eye protection. Muriatic acid is highly potent and can cause chemical burns upon contact with skin. Protect yourself adequately before starting the process.
- Wearing long-sleeved clothing and closed-toed shoes is advisable to prevent any acid contact with your skin.
- You can purchase muriatic acid from hardware stores or home improvement centers. Since it requires a considerable amount of acid to clean each shell, ensure you have enough for your needs.
Place the shell on a flat, stable outdoor surface. A large rock or scrap wood piece can serve as an ideal platform. Alternatively, you can lay the shell directly on the ground if a suitable work surface is unavailable.
- Never work with muriatic acid indoors due to inadequate ventilation and potential damage to household surfaces.
Apply sufficient acid to cover the shell's exterior. Upon contact, you'll notice bubbles forming, indicating the acid's reaction with mineral deposits on the shell's surface. Leave the acid on for 20-30 seconds until the fizzing ceases.
- The bubbling occurs due to the acid's reaction with the shell's sodium bicarbonate.
Pro Tip: To minimize splashing, hold the bottle just above the shell, and keep your arms and legs at a safe distance.
Thoroughly rinse the shell with clean water. Set up near a garden hose or outdoor tap for convenience. Alternatively, use a watering can or large container nearby. Ensure the water washes over the shell and surrounding area for 3-5 seconds.
- Do not touch or move the shell until after rinsing.
- A thorough rinse will remove most of the acid, making the shell safe to handle.
Vigorously scrub the shell with a wire brush. Employ short, forceful strokes across the entire exterior. The outer layer of sediment and debris should come off easily after being softened by the acid. Continue scrubbing until progress ceases, then repeat as necessary.
- Paua shells are exceptionally durable, so don't hesitate to exert pressure. The more you scrub, the better the results.
- Cleaning paua shells can be meticulous. Exercise patience and care throughout the process.
Utilize a hammer and chisel to remove stubborn buildup and unwanted elements. Older paua shells often accumulate thick layers of calcified lime, barnacles, and other growths. A few taps with a hammer and chisel will effectively remove these.
- A screwdriver can serve as an alternative if a chisel is unavailable.
- For deep-seated debris, consider using a slender tool like an ice pick.
Continue the process until the paua achieves the desired appearance. Multiple washes, rinses, and scrubbings may be necessary to completely rid the shell of foreign substances. With each iteration, more of its natural coloration will emerge.
- Overall, the project should take no more than a couple of hours.
Apply a coat of polyurethane to preserve the shell's shine. Once satisfied with the shell's appearance, dry it with a towel and place it on newsprint or paper towels. Proceed to spray both sides with polyurethane, allowing it to air-dry for 1-2 hours until touch-dry.
- Polyurethane will seal the shell's pores, enhancing its holographic colors with a glossy finish.
- This step is optional but helps maintain the shell's beauty over time.
Refining Heavily-Encrusted Shells
Protect yourself with a facemask or respirator and ear protection. Polishing paua shells involves grinding and sanding, producing significant dust. Prevent inhalation of particles by wearing protective gear. Working outdoors or in a well-ventilated area enhances safety.
- Consider wearing durable work gloves to shield against scrapes, although it's optional.
Important: Dust from mollusk shells can be toxic if inhaled.
Equip an angle grinder or power polisher with a low-grit grinding wheel. Use a coarse 40-50 grit pad initially. Ensure safety by switching off power and unplugging when changing wheels. If tools are unavailable, achieve a high-gloss finish with sandpaper and patience.
- An orbital sander is an alternative option.
Grind away the lime buildup on the shell's exterior. Apply light-to-moderate pressure with the polishing device. Hand sanding with 60-150-grit sandpaper is effective, although slower. Avoid excessive force to prevent shell damage.
- Paua shells naturally accumulate lime, aiding in camouflage and defense against predators.
Regularly wipe the shell with wet sandpaper. Clear surface dust to maintain visibility and reduce airborne particles. Moisture minimizes dust production during polishing. Alternative options include using a damp cloth, sponge, or immersing the shell in water.
- Ensure the shell remains wet when using wet polishing pads for cooling purposes.
Gradually transition to finer pads or sandpaper. After using a 40-50-grit pad to remove sediment, switch to 60-80-grit sandpaper, then to 150-220-grit polishing pad, and so on. This process may require 4-6 passes.
- Each finer pad enhances the shell's clarity and vibrancy.
- For an ultra-smooth finish, consider using a 300-grit polisher or higher.
Apply a coat of polyurethane to seal the paua's beauty. Ensure the shell is dry and dust-free. Place it on newsprint or paper towels, spray with polyurethane from multiple angles, and let dry for 1-2 hours.
- A clear coat enhances the shine and protects the shell from damage and deterioration.
Helpful Tips
- Finely-polished paua shells make excellent decorations for indoor and outdoor spaces.
- In various cultures, paua shells are used as ornamental bowls for gemstones and other attractive items.
Essential Supplies
Bleach Disinfection Method for Paua Shells
- 5-gallon (19 L) bucket or similar large container
- Water
- Chlorine bleach
- Rubber or nitrile gloves
- Mild liquid dish soap
- Absorbent towel
- Metal tongs (optional)
Muriatic Acid Shell Polishing Technique
- Facemask or respirator
- Rubber gloves
- Protective eyewear
- Muriatic acid
- Wire brush
- Hammer and chisel
- Garden hose
- Clear spray-on polyurethane
- Long-sleeved clothing (optional)
- Watering can, pitcher, large bottle, or similar container (optional)
- Ice pick (optional)
Removing Stubborn Deposits from Shells
- Facemask or respirator
- Ear protection (muffs or plugs)
- Angle grinder, power polisher, or orbital sander
- Coarse grinding wheel
- Rotary polishing pads or sandpaper (various grits)
- Wet sandpaper
- Clear spray-on polyurethane
- Damp cloth or sponge (optional)
- Large water container (optional)
