---
title: "System of Edo Silver Coins"
url: "https://ittendo.com/en/coinpedia/edo-silver-001-overview"
site: "ITTENDO"
type: "coinpedia"
category: "edo-silver"
series: "Edo Silver Coins"
lang: "en"
---
# System of Edo Silver Coins

> Conclusion: Understanding the two systems (weighed and counted) and complex fineness changes of Edo silver coins, along with appraisal points and market prices, enables smart collecting and investing.

- 時代: 江戸
- 素材: 銀
- 額面: 朱 / 分
- 発行量: 通常
- 価格帯: 普及

## Two Lines of Edo Silver Coins: By Weight and Count

The silver coins circulated during the Edo period are broadly divided into two lines: "by weight silver coins (hyou-ryou ginka)" and "by count silver coins (keisuu ginka)". These two lines had clear differences in how their value was determined and the main regions where they circulated.

By weight silver coins are those whose value is determined by their weight, as the name suggests. Representative examples include Chōgin and Mameita-gin, which were mainly used in commerce centered around the Kansai region (Osaka) and Western Japan. Merchants measured the weight of the silver coins and inspected their purity in each transaction.

In contrast, by count silver coins refer to coins with a fixed denomination. These include Ichibu-gin and Nishū-gin, which circulated widely as auxiliary currency to gold coins in Eastern Japan, particularly in Edo. Towards the end of the Edo period, the issuance volume increased, making them indispensable for everyday payments by commoners. Understanding these two lines, alongside the [Introduction to Edo Gold Coins (Koban and Ōban)](/coinpedia/edo-gold-001-overview), is the key to unraveling the complex monetary system of the Edo period.

## Representatives of By Weight Silver Coins: Chōgin and Mameita-gin

Chōgin is a silver ingot roughly 10-15 cm in length with a sea cucumber-like shape, marked with stamps such as "Daikokuten" and the era-stamp "Jōze" indicating the period. These stamps served as a certification of quality guaranteed by the Ginza mint. Due to their high value per piece, Chōgin was used in high-value transactions.

Mameita-gin, a smaller cut version of Chōgin, was used for change or small transactions. Like Chōgin, these were stamped and were also known as "pebble silver" due to their shape. The silver purity of these by weight silver coins fluctuated with policies of different administrations. For example, Chōgin from the Keichō period (1601–) boasted about 80% silver purity, but the purity could drop to as low as 20% by the end of the Edo period.

Chōgin and Mameita-gin possess a unique charm differing from modern currency due to their irregular shapes and weight-based value determinations. Particularly, the types and conditions of the stamps are important appraisal points for collectors. Further details about these coins can be explored in the [Detailed Explanation of Chōgin](/coinpedia/edo-silver-002-chogin).

## Spread of By Count Silver Coins: Ichibu-gin and Nishū-gin

The foremost representative of by count silver coins is Ichibu-gin, a rectangular silver coin first minted in Tenpō 8 (1837). Its value was fixed at one-fourth of a Koban, clearly defining its exchange rate with gold coins. This established a division of roles where gold coins were used for large transactions, while silver coins were utilized for medium and small transactions.

Nishū-gin, valued at half that of Ichibu-gin, began issuance in the Bunsei period. The particularly high-purity and beautifully designed Nanryō Nishū-gin is noteworthy. Due to their fixed denominations, these by count silver coins required no weighing, making them extremely user-friendly for commoners.

With the opening to foreign trade in the late Edo period, these coins were also used in international trade settlements, increasing their significance. The variety was abundant, and like the [Types and Price Ranges of Koban](/coinpedia/edo-gold-002-koban-types), the value varied greatly depending on their issuance period and purity. Understanding the characteristics of each era is crucial when collecting.

## Overview of Silver Purity Changes and Economic Impact

The changes in the purity of Edo silver coins were closely linked to the financial conditions of the shogunate. While Keichō Chōgin (1601–) started with about 80% silver purity, it gradually decreased to about 64% during the Genroku recoinage (1695) and about 50% in the Hōei recoinage (1706). This drop in purity prompted price inflation due to variations in currency value, which became a factor pressuring the livelihoods of commoners.

In the reforms of the Shotoku and Kyōhō eras (1714–1736), the silver purity temporarily rebounded to about 80%, aiming for economic stability. However, after the Genbun recoinage (1736), the purity declined again, reaching as low as about 26.1% in Tenpō Chōgin (1837–) by the end of the Edo period. Conversely, there were high-purity by count silver coins like Ansei Ichibu-gin (1859–) set at about 87.3%, demonstrating significant variance in purity depending on the type and purpose.

Understanding this complex history of purity changes is essential for gaining insight into the historical background and market value of Edo silver coins. A perspective on how the socio-economic conditions and monetary policies of each era influenced silver coin purity is necessary to read these facts.

## Background of Recoinage: Shogunate's Financial Distress and the Temptation of 'Deme'

The primary reason the shogunate repeatedly lowered the purity of silver coins lies in chronic financial distress. Lowering the purity allowed more coins to be minted from the same amount of bullion, and the profit from the difference was called "deme". This deme was an effective means of providing temporary financial income to the shogunate.

Ogiwara Shigehide, the accounting officer who led the Genroku recoinage, actively promoted this deme policy, temporarily stabilizing the shogunate's finances. However, the reduction in coin purity meant a decrease in currency value, leading to inflation and soaring prices. This vicissitude hit the livelihoods of low-income commoners particularly hard, and a cycle of social instability recurring from mid- to late-Edo period ensued.

Recoinage was not merely a currency policy but a mirror reflecting the politics, economy, and social conditions of the time. Understanding this historical background allows for assessing not only rarity and preservation, which are key factors in determining the [Value of Ancient Coins](/coinpedia/basics-001-value-drivers), but also the narratives these coins hold.

## Basics of Weight and Dimensions: The First Step in Authenticity Determination

The physical specifications of Edo silver coins vary significantly by type. Chōgin, a by weight silver coin, shows a large variation, with weights typically ranging from 120-180g and lengths of about 10-15cm. Mameita-gin is smaller, ranging approximately from 2-10g.

In contrast, by count silver coins are standardized and serve as vital benchmarks for determining authenticity. For instance, the standard specs for the representative Tenpō Ichibu-gin are 26mm in height, 16mm in width, and 8.66g in weight. Nanryō Nishū-gin is standardized at around 30mm by 18mm and weighs about 5g. Deviations from these standards may indicate forgeries or altered items.

Using precise scales (accurate to 0.01g) and calipers for measurement is the first step in verifying the authenticity of by count silver coins. Notably, even minute differences in weight or dimensions can serve as decisive evidence distinguishing genuine from counterfeit items, as highlighted in the [Guide to Detecting Fakes and Alterations](/guide/fake-detection).

## The First Step in Appraisal: Checkpoints and Tools for Beginners

In appraising Edo silver coins, particularly by count silver coins, beginners should initially check three points. The first is "weight." Measure it with a precision scale (to 0.01g) and compare with the standard specifications for the type. Significant deviations from standard values may suggest forgeries or alterations.

The second point is "dimensions." Use calipers to measure height and width accurately, comparing with known specifications. Again, standardized coins should fall within specific ranges. The third is checking the "engraving of stamps." Genuine stamps exhibit clear edges and depth, achieved through hammering, but modern forgeries often display softer outlines and shallower engravings.

Precision scales, calipers, and high magnification loupes or magnifiers are essential for these checks. Chōgin and Mameita-gin allow for some judgment based on the liveliness of stamps and silver color, despite lacking stringent standards like by count silver coins. More detailed appraisal standards can be found in [Coin Grading Standards](/coinpedia/basics-003-grading).

## Exit Strategy and Reality of Monetization: Smart Selling Methods

The main outlets for selling Edo silver coins are specialized coin auctions, specialized coin dealers, and antique markets. Each has its advantages and disadvantages, and the optimal choice varies depending on the type and condition of the coins you own.

Tenpō Ichibu-gin and other widely circulated by count silver coins have relatively high liquidity due to their large buyer base. Bringing these to specialized dealers or using online buying services is feasible. Conversely, Chōgin and certain rare Mameita-gin have a limited buyer pool, often making their sale more time-consuming. Such high-value or rare items can expect the highest sale prices at large-scale specialized coin auctions.

The basic sales strategy involves obtaining valuations from multiple specialized dealers in advance and selling to the highest bidder. Furthermore, a certificate of appraisal from a trusted appraisal organization increases buyer confidence and often leads to higher selling prices. Refer to [Introduction and Utilization of Coin Auctions](/coinpedia/basics-007-auction) to explore the best selling method for your coins.

## The Reality of Fakes and Altered Items: Knowledge to Mitigate Risks

Counterfeits of Edo silver coins are broadly divided into two types. One is the "han-zou" Ichibu-gin and Nishū-gin unofficially minted by various domains during the Edo period. These often differ in purity or shape from officially sanctioned coins of the shogunate, and while some now hold rare value, they are distinctly separate from authentic currency.

The other type is "modern forgeries" fabricated after the Edo period. These are intentionally made to resemble authentic coins, often deviating in weight or dimensions from standards. Additionally, there are "altered items" where original silver coins are modified to enhance their value, such as by adding stamps or polishing the surface to improve appearance.

To avoid these risks, prioritize purchasing coins with a certificate of authenticity from a trustworthy organization, such as the Japan Numismatic Dealers Association (JNDA). Also, approach suspiciously cheap items of unknown origin with caution, and equipping yourself with knowledge from the [Guide to Detecting Fakes and Alterations](/guide/fake-detection) is vital for safe collecting and investing activities.