# Finding Watermarks

Part of the Stamp Collecting Merit Badge Digital Resource Guide: [Introduction & Overview](https://merit-badge.university/merit-badges/stamp-collecting/guide/index.md)

*5. Collector's Tools*

> **5g.** Watermark fluid

A watermark is a design pressed into stamp paper during manufacturing. Sometimes it is invisible until you use a watermark detector dish and watermark fluid. The merit badge pamphlet explains that this hidden mark can help identify the exact stamp issue.

### What the tool does

The stamp is placed in a dark tray or dish, and a small amount of watermark fluid is used to make the paper's hidden design easier to see. The watermark may appear as lighter or darker shapes for a moment.

### Why collectors use it

Some stamps look identical on the front but have different watermarks. If the catalog lists more than one possibility, the watermark can help you choose the correct entry.

Video: [How to Find Watermarks on Stamps (video)](https://youtu.be/Ury0mawE7m4?si=ctCOkAPh6V_GB22X)

> **Safety First!**
>
> Use watermark fluid only with adult guidance, good ventilation, and the exact safety directions that come with the product. Handle only a small amount, avoid eye contact, and keep it away from flames and heat.

> **Tip**
>
> Demonstrate this tool on a common stamp, not a valuable one. The point is to show the process safely and clearly.

You have finished the tools section. Next, you will use those skills to mount stamps in an album and protect a collection for the long term.

---

- Previous: [Safe Storage Sleeves](https://merit-badge.university/merit-badges/stamp-collecting/guide/req5f/index.md)
- Next: [Mounting and Protecting a Collection](https://merit-badge.university/merit-badges/stamp-collecting/guide/req6/index.md)