Which of the following is not a carbonate ore?

Options

A. Dolomite
B. Calamine
C. Siderite
D. Zincite

Explanation

To determine which of the following is not a carbonate ore, we will analyze each option provided.

### Step 1: Identify the first ore - Dolomite
- **Description**: Dolomite is a mineral composed of calcium magnesium carbonate.
- **Chemical Formula**: It is represented as MgCO3.CaCO3.
- **Conclusion**: Since it contains carbonate ions (CO3), Dolomite is a carbonate ore.

### Step 2: Identify the second ore - Calamine
- **Description**: Calamine is primarily known as an ore of zinc, but it also contains iron.
- **Chemical Formula**: It is represented as Fe2O3.ZnO.
- **Conclusion**: Calamine does not contain carbonate ions; it is an oxide ore, not a carbonate ore.

### Step 3: Identify the third ore - Siderite
- **Description**: Siderite is a mineral that serves as an iron ore.
- **Chemical Formula**: It is represented as FeCO3.
- **Conclusion**: Since it contains carbonate ions (CO3), Siderite is a carbonate ore.

### Step 4: Identify the fourth ore - Zincite
- **Description**: Zincite is a mineral that is primarily composed of zinc oxide.
- **Chemical Formula**: It is represented as ZnO.
- **Conclusion**: Zincite is not a carbonate ore; however, it is often confused with carbonate ores due to its association with zinc.

### Final Conclusion
- Among the ores discussed, **Calamine** is the only one that is not a carbonate ore. It is an oxide ore of iron and zinc.

### Answer: Calamine is not a carbonate ore.

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