Your Coin Holder Is Closed—but Is It Really Sealed?

How a built-in vacuum pump creates a different kind of coin-storage environment*

Coin holders are commonly used to separate coins from direct handling and the surrounding environment. Numismatic Hermetics was created around a more specific idea: a coin holder can do more than close around a coin. It can create a vacuum-tight environment around it.

That idea led to the development of the patent-pending Numismatic Hermetics Vacuum Coin Storage Device. The device is designed for collectors who want protection beyond a standard holder. Its central feature is a built-in vacuum pump that removes air from inside the case and creates a hermetic seal.

Closing a holder and creating a seal

The distinction behind the product is expressed in a simple statement: **A closed coin holder is not necessarily a sealed coin holder.

A standard holder closes around a coin. The Numismatic Hermetics device is designed to create a vacuum-tight storage environment. Its pump is built directly into the case, so the user does not need a separate pump or additional equipment.

After placing a coin inside and closing the case, the user presses the built-in pump to create the vacuum. The pump can be pressed multiple times to deepen the vacuum. According to the product specifications, the device creates a vacuum environment at approximately 5 PSI below atmospheric pressure.

This process gives the collector an active role in sealing the case. Instead of only closing a lid, the user operates the integrated pump to create the intended storage environment.

Designed to address the air surrounding a coin

Numismatic Hermetics product materials identify several elements that the vacuum-tight environment is designed to address:

- Moisture
- Oxygen
- Sulfur dioxide
- Hydrogen sulfide
- Dust, particulates, pollutants, and other airborne contaminants

The device removes air from the case before maintaining the seal. It is designed to remove moisture from the storage environment, exclude oxygen, remove sulfur dioxide and hydrogen sulfide, and keep airborne contaminants from entering the sealed space.

These features address the environment immediately surrounding the stored coin. The product's purpose is not limited to providing a physical cover. Its design focuses on creating and maintaining a vacuum-tight space inside the case.

An integrated and compact design

The built-in pump is an important part of the device's practicality. Because the pump is incorporated into the case, there is no separate component to connect, carry, or store.

The case measures approximately 84 millimeters long, 58 millimeters wide, and 9 millimeters deep. It weighs approximately 37 grams. These dimensions allow the vacuum system to remain part of a compact individual coin-storage device.

The user can place the coin in the case, close it, and operate the pump directly on the device. The complete sealing process is contained within the holder itself.

Materials selected for coin storage

The materials used around a coin are part of the product's design. The Numismatic Hermetics device is made with non-reactive, archival-safe plastic and gaskets. These components form the case and support its vacuum-tight seal.

The gasket and plastic are not presented as secondary accessories. They are part of the complete storage system, working with the built-in pump and case structure to create the intended environment.

Airtight and watertight when properly sealed

According to the product materials, the Numismatic Hermetics device is airtight and watertight when properly sealed. The company has demonstrated the closed device with water poured and sprayed over it, followed by a dry-coin reveal.

The water demonstration is intended to show the performance of the properly closed and sealed case during that demonstration. It should not be interpreted as a guarantee against every possible storage condition, form of damage, or length of exposure.

What makes the approach different

The difference is the combination of features in one individual coin-storage device:

1. The coin is placed inside the case.
2. The case is closed.
3. The built-in pump is pressed to remove air and create the vacuum.
4. The vacuum-tight seal maintains the intended environment around the coin.

The system does not require a separate pump. Its patent-pending valve and integrated-pump design allow the collector to perform the sealing process directly on the case.

The product is designed to provide:

- A built-in vacuum pump
- A vacuum-tight hermetic seal
- An environment approximately 5 PSI below atmospheric pressure
- Removal of moisture from the storage environment
- Removal of sulfur dioxide and hydrogen sulfide
- Exclusion of oxygen
- Protection from airborne dust, particulates, and pollutants
- Airtight and watertight performance when properly sealed
- Non-reactive, archival-safe plastic and gaskets
- A compact, lightweight case

A product developed for collectors

The Numismatic Hermetics Vacuum Coin Storage Device was developed for coin collectors seeking a storage option beyond a standard closed holder. Its design brings the case, gasket, valve, and pump together in one compact device.

Its purpose can be summarized by one question: Is the coin holder merely closed, or has it created a sealed environment around the coin?

Numismatic Hermetics was designed to provide the second option. By incorporating the vacuum pump into the case, the device allows the collector to create a vacuum-tight, hermetic environment without separate equipment.

The result is a different approach to individual coin storage—one focused not only on covering the coin, but also on the environment inside the holder.

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Author Disclosure:

Peter Kristiansen is affiliated with Numismatic Hermetics, the developer of the patent-pending Vacuum Coin Storage Device discussed in this article. The product descriptions and performance statements in this article are based on Numismatic Hermetics company materials. They are not presented as the findings of an independent laboratory or conservation study.

This draft intentionally relies only on information contained in Numismatic Hermetics product and company materials. No outside preservation claims, humidity recommendations, conservation instructions, or independent performance conclusions have been added.

Visit our website: https://www.numismatichermetics.com