In Islamic law, currencies that are considered to be Sharia-compliant are those that do not involve prohibited elements such as usury, fraud, or excessive speculation. Here are some currencies that are considered acceptable to use:

### 1. **Traditional Currencies**

- **Paper currencies**: such as the US dollar, the euro, the British pound, and other national currencies that do not include usurious elements.

### 2. **Cryptocurrencies**

- **Cryptocurrencies**: Some cryptocurrencies can be considered halal if they are used in a way that complies with Sharia, such as:

- **Bitcoin**: It is considered acceptable in some opinions, provided that it is used responsibly and without falling into usury.

- **Ethereum**: It is also considered acceptable if used in a Sharia-compliant manner.

### 3. **Gold and Silver**

Precious metals such as gold and silver (although not currencies in the traditional sense) are acceptable under Sharia and can be used as instruments for trading and investment.

### 4. **Asset-Backed Currencies**

- Currencies that are backed by real assets or commodities, such as gold-linked currencies, can be considered halal.

### General principles:

- **Avoid usury**: Currencies should not include any usurious interest.

- **Fair Terms**: The trading and use conditions of currencies must be fair and not involve exploitation or fraud.

**Transparency**: There should be transparency in transactions and no ambiguity.

### a summary

It is important to consult religious scholars or Islamic law experts to obtain an accurate fatwa on which currencies can be used, especially in the case of cryptocurrencies that are still subject to debate.