Preserving the 1993 New Zealand Kingfisher $2 Coin: A Conservationist’s Guide

Introduction: Preserving Your 1993 Kingfisher Coin’s Value

As a seasoned collector who’s handled countless specimens, I’ve seen too many valuable coins ruined by improper cleaning or storage. The 1993 New Zealand Kingfisher $2 coin, with its distinctive security edge and aluminum-bronze composition, demands thoughtful preservation to maintain its numismatic value for future generations.

Understanding the Alloy: Aluminum-Bronze Composition

This 1993 Kingfisher coin is struck from aluminum-bronze, an alloy containing approximately 92% copper, 6% aluminum, and 2% nickel. This composition creates the coin’s distinctive golden color and provides excellent durability for circulation.

Unlike plated or clad coins, these are solid alloy throughout – the same composition extends from edge to edge. This is crucial to understand because it means the coin cannot be “re-plated” or restored to original appearance through surface treatments.

Why Aluminum-Bronze Develops Toning

The copper content in aluminum-bronze makes these coins particularly susceptible to toning over time. When exposed to air, moisture, and environmental contaminants, copper naturally forms various oxide compounds that create the characteristic rainbow hues many collectors prize.

Never attempt to remove toning from an aluminum-bronze coin. The toning is a natural protective layer that forms on the surface, and aggressive cleaning will almost certainly damage the coin’s surface and significantly reduce its value.

Identifying and Preventing PVC Damage

One of the most serious threats to aluminum-bronze coins is PVC (polyvinyl chloride) damage. PVC was commonly used in coin flips and storage pages until collectors became aware of its destructive properties.

Symptoms of PVC Damage

PVC damage manifests as a distinctive green, slimy residue that forms on the coin’s surface. This occurs when PVC deteriorates and releases hydrochloric acid, which reacts with the copper in the alloy. Once PVC damage occurs, it is extremely difficult to reverse and often permanently mars the coin’s surface.

Proper Storage Solutions

To prevent PVC damage, store your 1993 Kingfisher coin in archival-quality holders made from materials like Mylar, polyethylene, or other inert plastics. Avoid any storage products that have a strong plastic smell, as this often indicates PVC content.

• Use 2×2 cardboard holders with Mylar windows
• Store in acid-free coin albums or folders
• Consider air-tight capsules for premium specimens
• Maintain stable temperature and humidity levels

The Security Edge: A Unique Feature Requiring Special Care

The 1993 Kingfisher coin features a distinctive security edge with a ribbed center stripe and rivets. This edge design, common in coins from Hong Kong and India, was originally intended to prevent clipping and counterfeiting.

The security edge creates additional surface area where toning and oxidation can occur. Pay special attention to cleaning the edge area if necessary, but remember that any cleaning should be minimal and conservative.

Cleaning: When and How to Proceed

The fundamental rule of coin conservation is: never clean a coin unless absolutely necessary. For circulated coins with dirt or debris, gentle cleaning with distilled water may be acceptable, but this should be done with extreme caution.

If cleaning becomes necessary:

1. Use only distilled water and a soft, lint-free cloth
2. Never use commercial coin cleaners or abrasives
3. Avoid touching the coin’s surface with bare fingers
4. Dry thoroughly with compressed air or by allowing to air dry on a soft surface

For valuable or rare specimens, professional conservation is always recommended over DIY cleaning attempts.

Understanding the Two-Tone Effect

Many collectors notice a distinctive two-tone appearance on their 1993 Kingfisher coins, with lighter areas appearing on high points like the Queen’s portrait and along rims. This is not a coating or plating issue, but rather the natural result of how aluminum-bronze oxidizes.

The alloy’s composition creates areas of slightly different metallurgical properties across the coin’s surface. When exposed to environmental factors, these areas tone at different rates, creating the characteristic highlight effect that many collectors find appealing.

Environmental Factors Affecting Toning

Several factors influence how your coin will tone over time:

• Humidity levels in storage environment
• Air quality and presence of pollutants
• Proximity to other metal objects
• Duration of exposure to open air

Storage Recommendations for Long-Term Preservation

Proper storage is the single most important factor in preserving your 1993 Kingfisher coin. Here are specific recommendations based on the coin’s unique characteristics:

Short-Term Storage

For coins you handle frequently or use for reference:

• Archival-quality 2×2 holders
• Acid-free envelopes
• Avoid PVC-containing products

Long-Term Storage

For coins you wish to preserve for decades:

• Air-tight capsules with silica gel desiccant
• Climate-controlled storage environment
• Individual compartments to prevent contact with other coins

Display Considerations

If you wish to display your coin:

• Use UV-filtering display cases
• Avoid direct sunlight exposure
• Maintain stable temperature and humidity
• Consider rotating display items to minimize exposure time

Authentication and Verification

The 1993 Kingfisher coin exists in both bronze-plated aluminum (KM#87) and silver proof (KM#87.a) varieties. When acquiring coins for your collection, proper authentication becomes crucial.

Key authentication points include:

• Correct weight for the alloy type
• Proper edge reeding and security stripe
• Sharp detail in high points of design
• Appropriate toning for the coin’s age and storage history

Professional Grading Considerations

For valuable specimens, consider professional grading services. However, be aware that grading standards for modern NCLT (Non-Circulating Legal Tender) coins can be more stringent than for classic numismatic pieces.

Conclusion: Preserving History for Future Generations

The 1993 New Zealand Kingfisher $2 coin represents an interesting chapter in modern numismatics – a commemorative piece that bridges the gap between circulating coinage and collector-oriented issues. Its unique security edge, aluminum-bronze composition, and distinctive toning characteristics make it a fascinating study for collectors and conservationists alike.

By following proper preservation techniques – avoiding cleaning, using appropriate storage materials, and understanding the natural toning processes of aluminum-bronze – you can ensure that your Kingfisher coin remains in excellent condition for future collectors to study and appreciate. Remember, the goal of conservation is not to make a coin look “perfect” but to preserve its authentic character while preventing damage from environmental factors.

The toning that develops on these coins over time is not damage but rather a natural patina that tells the story of the coin’s journey through time. Embrace these characteristics as part of the coin’s history, and focus your preservation efforts on preventing the types of damage that truly diminish a coin’s value and historical significance.

Related Resources

You might also find these related articles helpful:

• Grading One of the strangest modern coins yet minted: The Difference Between $10 and $1,000 – The New Zealand 1993 Two Dollar Kingfisher: A Professional Grading Perspective Condition is everything. Here is how to l…
• Is Your 1993 New Zealand $2 Kingfisher Coin Real? Authentication Guide – Historical Significance The 1993 New Zealand $2 Kingfisher coin marks a fascinating chapter in modern numismatics. As on…
• How to Spot Rare Errors on One of the Strangest Modern Coins Yet Minted – Historical Significance Most collectors overlook the subtle details that can transform an ordinary coin into a numismati…