Cleaning and preserving ancient coins requires patience, care, and a deep respect for history

These coins are not just pieces of metal—they are windows into the past, carrying the marks of empires, trade routes, and everyday life from centuries ago

The first and most important rule is never to clean an ancient coin with harsh chemicals, abrasive tools, or even regular household cleaners

Improper cleaning may scar the metal, dissolve ancient surface layers, and erase evidence that scholars depend on to date and interpret the coin

Begin your assessment using bright, natural light and a high-quality loupe or magnifier

Look for signs of corrosion, dirt buildup, or previous attempts at cleaning

When thick layers of earth or calcification cover the surface, resist the urge to scrape or brush aggressively

Submerge the coin in pure, mineral-free water and allow time to work naturally

Distilled or deionized water is essential to prevent unwanted chemical reactions with the coin’s alloy

Refresh the soaking solution every 24 hours to encourage gradual cleaning

A few experts employ a clean, ultra-soft bristle brush—such as a new, アンティーク コイン unused cosmetic brush—to dislodge surface grit, provided the coin is intact

Never use vinegar, lemon juice, baking soda, or any acidic or alkaline solution

They risk dissolving fine details, corroding the metal, and permanently altering the coin’s appearance

Never trust a jewelry cleaner with a coin that is over a thousand years old

If the coin has green or blue corrosion, known as patina, this is often a sign of age and should be left alone

Preserving the patina often means preserving the coin’s long-term stability

After any gentle cleaning, dry the coin thoroughly with a soft, lint-free cloth

Avoid attics, basements, or windowsills where temperature and humidity fluctuate

Use acid-free paper or plastic holders designed for coin storage

Always check labels—only use "PVC-free" storage materials

Store coins in airtight containers with desiccants to maintain low humidity

Professional conservators have the expertise and tools to evaluate and stabilize fragile ancient coinage safely

Experts use microscopes, controlled environments, and non-invasive techniques to stabilize without altering

The true objective is preservation, not restoration—let the coin speak for itself

The most valuable ancient coins are those that have survived with their original surfaces intact

By respecting its origins, you become a guardian of its legacy, ensuring future generations can learn from it