Which of the following ores can be considered as an ore of both Ca and Mg?

Options

A. Dolomite
B. Cailcte
C. Magnesite
D. Magnetite

Answer

To determine which of the given ores can be considered as an ore of both calcium (Ca) and magnesium (Mg), we need to analyze the chemical composition of each ore listed.

### Step-by-Step Solution:

1. **Identify the Ores**: The ores mentioned in the question are:
- Dolomite
- Calcite
- Magnetite

2. **Write the Chemical Formulas**:
- **Dolomite**: The chemical formula for dolomite is \( \text{CaMg(CO}_3\text{)}_2 \). This indicates that dolomite contains both calcium (Ca) and magnesium (Mg).
- **Calcite**: The chemical formula for calcite is \( \text{CaCO}_3 \). This indicates that calcite contains only calcium (Ca) and does not contain magnesium (Mg).
- **Magnetite**: The chemical formula for magnetite is \( \text{Fe}_3\text{O}_4 \). This indicates that magnetite contains iron (Fe) and does not contain either calcium (Ca) or magnesium (Mg).

3. **Analyze the Ores**:
- **Dolomite**: Contains both calcium and magnesium.
- **Calcite**: Contains only calcium.
- **Magnetite**: Contains neither calcium nor magnesium.

4. **Conclusion**: From the analysis, we can conclude that the only ore that contains both calcium and magnesium is dolomite.

### Final Answer:
The ore that can be considered as an ore of both calcium and magnesium is **Dolomite**.

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