You bought an antique coin for ¥1,000,000, but when it comes time to sell, there are no buyers — that kind of tragedy is not uncommon.

The value of an antique coin is determined not by the "market price" but by the "price at which it actually sells."

What creates that gap is "liquidity" — the factor investors overlook most.

What Is Liquidity? — The Distance Between Market Price and Reality

A curious phenomenon occurs in the world of antique coin investment.

Even for coins of the same grade and the same issue, one person sells at the expected price while another is forced to accept a steep discount.

What determines that difference is "liquidity."

Liquidity, put simply, is an indicator of "how quickly and how close to the market price you can sell when you want to sell."

In stock markets, liquidity has been studied exhaustively, but in the antique coin market it has been almost entirely ignored.

As a result, novice investors are often shocked by the gap between "the price shown on a market chart" and "the price at which the coin can actually be sold."

The Trading Structure of the Antique Coin Market — Why Liquidity Arises

[For Beginners] Whether the Market Has "Depth" or Is "Thin"

In the antique coin market, trading volume varies dramatically by issue.

As you can see from Basics of Antique Coin Auctions, there is a bias in the hammer-price data from major auction houses.

Popular issues — for example, fine-grade Tenpō Tsūhō (天保通宝) or specific year dates of Meiji gold coins — generate multiple transactions every month.

On the other hand, for minor coin types or low-grade ranges, there may be only one transaction every few months, or even just one per year.

This "depth of trading" is what drives liquidity.

In zones with high trading volume, buyers and sellers are always present in the market, making it easier for a "market-rate price" to be achieved at the time of sale.

In zones with low trading volume, however, your sale may require waiting "until a buyer appears," and during that time the market may move, or the buyer who does appear may demand a discount — both risks increase.

[For Intermediate Readers] The Asymmetry of Supply and Demand and the Trap of "Thin Trading"

When watching auction prices, you often hear the expression "a data point appeared."

This means "one hammer-price transaction occurred," but for issues with extremely few transactions, that single data point ends up functioning as the "market price."

For example, suppose a particular antique coin has had only three hammer-price transactions over the past three years: ¥100,000, ¥120,000, and ¥110,000.

The average is ¥110,000, but in reality each transaction was nothing more than an individual trade that happened to find a buyer at that specific moment.

Even if you try to sell today, if there is no buyer, that ¥110,000 is not a "market price" — it is merely a "wish."

Conversely, for an issue with more than ten transactions per month, multiple buyers are always present, which means that when you sell, there is a higher likelihood of being able to negotiate a price with those buyers.

This is the reality behind the saying: "issues with high liquidity tend to sell at market price."

[For Advanced Readers] Capital Flows and the Identity of Buyers

Looking even deeper, what determines liquidity is the question of "who is buying."

The antique coin market has roughly three layers of buyers:

  1. Collector layer: Researchers who study specific issues or eras deeply and will pay high prices. However, their numbers are limited.
  1. Investor layer: Those who buy based on relative undervaluation or expectations of price appreciation. Sensitive to trading volume.
  1. Dealer layer: Those who purchase for resale purposes, looking for a profit margin.

Issues with a thick collector layer — for example, rare varieties of a particular Kan'ei Tsūhō (寛永通宝) — can experience large price swings, but because passionate buyers exist, liquidity tends to be maintained.

Issues supported only by the investor layer, on the other hand, can fall into a "liquidity crisis" in which buyers vanish all at once when prices decline.

Issues with a thick dealer layer always attract purchasing activity and therefore have high liquidity, but because market prices are easily established, there is a risk that when an individual sells, the price offered will be discounted to the "dealer buying price."

Real-World Examples of High-Liquidity and Low-Liquidity Issues

High-Liquidity Issues (Multiple Transactions Per Month)

Because transactions are frequent for these issues, there is a high likelihood of achieving a sale close to "this month's market price" at the time of sale.

Low-Liquidity Issues (One to a Few Transactions Per Year)

  • Koban issued by regional feudal lords during the Edo period, or coin types cast in extremely limited quantities
  • Issues of which extremely few were produced for a specific year and mint combination
  • The ultra-high-grade range of MS70 and above (where the pool of buyers is limited)

For these issues, when it comes time to sell, you are often forced to choose between "waiting until a buyer appears" or "accepting a discount."

How to Read Liquidity from Market Charts

When checking price trends on market charts, there are points that beginners tend to miss.

Point 1: Count the "Number of Data Points"

Count how many data points appear on the chart for the past 12 months.

If there are 12 or more, that means "at least one transaction per month" — relatively high liquidity.

If there are 3 or fewer, the market is in a thinly traded state of roughly one transaction per year.

Point 2: Look at the "Spread" of Data Points

If the data points for the same grade range show large price variation, that is a signal that "liquidity is low and the market is easily swayed by individual transactions."

Conversely, if the data points are concentrated within a consistent price band, it suggests that "multiple buyers and sellers are forming the market," meaning liquidity is likely higher.

Point 3: The Gap Between the "Median" and the "Most Recent Price"

If the median of past transactions and the most recent single hammer price differ significantly, caution is warranted.

It means either "the market price has changed sharply" or "a single individual transaction is distorting the market price."

For issues with many transactions, the former is more likely; for issues with few transactions, it is the latter.

Liquidity Mistakes Beginners Commonly Make

Mistake 1: Using the "Highest Price" on the Market Chart as a Reference for the Purchase Price

This is the case of seeing information that "this issue once sold for ¥500,000" and then buying at close to ¥500,000.

However, that ¥500,000 may have been "a single transaction that occurred three years ago."

If no transactions have occurred since then, there is no guarantee that you can sell for ¥500,000 when you go to sell.

Mistake 2: Jumping at a Low-Grade "Bargain"

You see something like: "The market price for this issue at MS50 grade is ¥50,000, but here is one in that condition for ¥30,000" and you buy it.

However, if the MS50 grade for that issue sees only one transaction per month, you are prone to finding "no buyers" when you go to sell.

Mistake 3: Holding a Thinly Traded Issue Long-Term, Expecting the Market to Rise "Eventually"

Issues with low liquidity may see their market prices rise, but when it comes time to sell, you pay the cost of "waiting until a buyer appears."

If prices fall in the meantime, there is also the risk of locking in a loss.

Antique Coin Investment Strategies That Account for Liquidity

For Beginners: Start from "Zones with Many Transactions"

First, narrow your focus to issues and grade ranges that generate at least three transactions per month.

After understanding Antique Coin Grading Standards and How to Read Them, it is safe to target the MS60–MS65 range of "standard fine-grade" coins.

This zone has a thick pool of buyers and tends to allow sales close to market price.

For Intermediate Investors: Balance Liquidity Against Profit Margin

Even for issues with few transactions, there are cases where "the potential for future liquidity improvement" exists.

For example, if a particular coin type has recently been featured in the media or if a research paper has been published, collector interest may increase and liquidity may be reassessed.

Building a position before such a "liquidity reassessment" offers a large profit margin but also carries higher risk.

For Advanced Investors: Wait Until Multiple Transaction Data Points Appear

When assessing the market price of a thinly traded issue, it is wise to wait until "at least three transactions" — not just one hammer price — have been recorded.

By doing so, you eliminate the randomness of individual transactions and gain a more reliable picture of the market price.

ITTENDO's Conclusion: Use Liquidity as the Axis of Market Price Judgment

To avoid finding yourself "in trouble at the time of sale" in antique coin investment, you must ask at the time of purchase: "Can this issue actually be sold?"

The prices shown on market charts are, after all, "past transactions."

There is no guarantee that those market prices will be replicated when you go to sell.

For issues with few transactions in particular, the gap between market price and reality can be large.

Beginners should choose issues based not on "apparent undervaluation" or "expectations of future price appreciation," but on the criterion of "how many transactions per month are currently occurring right now."

Continuously monitoring after purchase to check whether "liquidity has changed" leads to risk management during long-term holding.

At ITTENDO, we make it possible to track the "current state" of antique coins based on past auction records and market charts.

For categories that interest you, monitoring prices in the Vault makes it easier not to miss changes in the market.

In particular, by catching the movements of issues whose liquidity is increasing — or conversely, issues whose trading volume is declining — your judgment about the right time to sell will become more accurate.

The Special Nature of Antique Coin Market Liquidity

The liquidity of the antique coin market has a unique structure that differs from other asset classes such as equities, bonds, and real estate. Transactions in the same issue may occur only a few times per year, which limits the choices available for the timing of a sale. From the perspective of market analysis covered in How to Read Antique Coin Market Charts Correctly, a liquidity assessment that is conscious of the difference between thin trading and genuine demand becomes important.

The Three Factors That Determine Liquidity

The factors that determine the liquidity of an antique coin can be organized into three. The first is the issue's name recognition: issues with high name recognition — such as Kan'ei Tsūhō (寛永通宝), Keichō Koban (慶長小判), and Meiji gold coins — tend to have high liquidity. The second is grade distribution: within the grading system covered in Antique Coin Grading Standards and How to Read Them, grades with higher circulation volume have higher liquidity. The third is market depth: issues backed by a larger domestic and international collector base have more stable liquidity.

Sale Routes and Time Required

There are three options for selling antique coins: auction, specialist dealers, and private transactions. Auctions, covered in Basics of Antique Coin Auctions, allow sales close to market price, but require several months from the time of consignment to the hammer fall. Selling to specialist dealers offers immediacy, but the buying price offered tends to fall below market price. Private transactions allow fees to be kept low, but finding a counterparty takes time.

The Problem of Whether You Can Sell When You Want To

The question of "can you sell when you want to?" is frequently discussed in relation to antique coin collection liquidity. For issues backed by genuine demand, if an appropriate route is chosen, selling is possible. However, there can be a gap between the desired price level and the actual market price, and it is this gap that can create the impression among collectors that a coin "cannot be sold."

Collection Strategies for Securing Liquidity

Collection strategies that are conscious of liquidity can take several directions. The first is a strategy centered on high-liquidity issues, incorporating well-known issues such as Meiji gold coins — covered in Meiji Gold Coin Boom Again? — and Keichō Koban (慶長小判) — covered in Key Points for Authenticating Keichō Koban. The second is a strategy that combines rare issues with issues in wide circulation, balancing overall liquidity against returns. The third is a strategy of building the collection entirely as cultural heritage holdings, on the premise of keeping them in hand for a very long time.

International Grading and Liquidity

Coins slabbed by international grading agencies have the characteristic of significantly enhanced liquidity. The trend of international grading covered in PCGS / NGC Grading and Evaluation of Japanese Antique Coins is an important structural factor from the perspective of liquidity as well. Because graded slab coins can be traded with confidence by collectors and specialist dealers both domestically and internationally, more selling opportunities arise.

Balancing Long-Term Holding and Liquidity

Even for cultural heritage collections built on the premise of keeping coins in hand for a long time, ignoring liquidity entirely is not realistic. From the risk management perspective covered in Risk Management in Antique Coin Investment, incorporating some high-liquidity issues into a portion of the portfolio prepares you for converting holdings to cash in an emergency.

The Relationship Between Liquidity and Price Formation

Liquidity and price formation in the antique coin market are closely related. For high-liquidity issues, price information is continuously updated, making market prices more reliable. For low-liquidity issues, prices are easily pulled upward by a single high hammer price, making the median market price difficult to grasp. Among the three perspectives on market analysis covered in How to Read Antique Coin Market Charts Correctly, transaction frequency and the gap from expected prices are the core elements of liquidity assessment.

Comparing Liquidity Between Domestic and Overseas Markets

The liquidity of the domestic market and overseas markets shows different characteristics depending on the issue. In overseas markets, covered in International Market Trends: Japanese Antique Coins Targeted by Overseas Buyers, there are cases where certain issues are traded more actively than in the domestic market. This reflects the preferences of overseas collector communities and is an important perspective in issue-by-issue liquidity assessment.

Summary

Collections That Are Conscious of Liquidity

The liquidity of antique coins is a characteristic of a unique asset class with properties distinct from equities or bonds. Understanding these properties and building a strategy suited to your collection goals and time horizon supports long-term collection activity. By combining the long-term storage infrastructure covered in Practical Guide to Storing Antique Coins and Managing Humidity with the liquidity perspective, strategic collection building becomes possible.

A Fundamental Understanding of Liquidity

Developing a fundamental understanding of antique coin liquidity is the foundation that supports the strategy of long-term collection activity. Rather than being driven about by short-term liquidity, the recommended approach is a balanced strategy that treats the activity as a long-term endeavor of cultural heritage stewardship while ensuring the necessary liquidity.

Collections That Take Liquidity Into Account

Understanding the unique nature of antique coin market liquidity is the foundation that supports the strategy of long-term collection activity. Rather than pursuing high liquidity alone, making issue selections suited to the goals and time horizon of your collection allows you to establish your own collection style. Incorporating the liquidity perspective into your collection strategy is recommended in combination with Basics of Antique Coin Auctions and Risk Management in Antique Coin Investment.

The unique nature of antique coin market liquidity is an important perspective when thinking about the long-term strategy of collection activity. By viewing the activity not as a short-term pursuit of liquidity but as a long-term endeavor of cultural heritage stewardship, a collection deepens into something that carries meaning both as an asset and as cultural heritage. Alongside the physical storage covered in Practical Guide to Storing Antique Coins and Managing Humidity, conscious issue selection from a liquidity perspective is also an important element of strategic collection building.

By making issue selections that account for liquidity and suit your collection goals and time horizon, the overall significance of your collection activity deepens. Balancing short-term and long-term considerations, liquidity and rarity, and nurturing a collection while maintaining that balance is the essence of twenty-first-century collection activity. Through a long-term dialogue with cultural heritage, you yourself also grow into a richer presence.

The liquidity perspective is an indispensable viewpoint when thinking through the overall strategy of a collection, but it is not something that should be used as the sole basis for judgment. By synthetically combining multiple perspectives — the value as cultural heritage, your own areas of interest, long-term enjoyment — and establishing your own collection style, you arrive at the outcomes that matter in the end.

Collection activity is a long-term endeavor of cultural heritage stewardship. Understanding the liquidity problem while maintaining the attitude of deepening the value of cultural heritage over time is what leads to the final outcome. Building the storage infrastructure for long-term holding, exchanging information with fellow collectors, the enjoyment of research — all of these combine to deepen the significance of collection activity.

By establishing a collection strategy that is conscious of liquidity, you realize an activity with a balanced long-term risk-return profile. Let us continue to dig deeper into this theme going forward.

The discussion of liquidity is a theme that forms the foundation supporting the overall strategy of collection activity. Let us continue to engage with it as an important field that will keep developing, from a long-term perspective.

The essence of collection activity lies in a dialogue with cultural heritage.