When mollusks appear on coins, it is typically just the empty shell. Occasionally we get the entire animal, as shown on this first official coin from Timor-Leste.
There are six known species of nautilus, the most famous being the chambered nautilus. Use of nautilus shells goes way back in Timor-Leste, with archeological evidence for pigmented and worked shells dating back 42,000 years. [SOURCE]
The fact that the coin depicts a live animal suggests that they were (are?) an important food source.
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