Which is not a silver ore ?

Options

A. Argentite
B. Siderite
C. Horn silver
D. Ruby silver

Explanation

To determine which of the given options is not a silver ore, we need to analyze each option and identify whether it contains silver or not.

### Step-by-Step Solution:

1. **Identify the Options**: We have four options to consider. Let's denote them as:
- Option A: Urgentite
- Option B: Siderite
- Option C: Ruby Silver
- Option D: Another ore (not specified in the transcript)

2. **Analyze Option A: Urgentite**:
- Urgentite is known to contain silver. Its chemical formula is Ag2S, which indicates the presence of silver (Ag).
- Conclusion: Urgentite is an ore of silver.

3. **Analyze Option B: Siderite**:
- Siderite is an iron ore with the formula FeCO3. It does not contain silver.
- Conclusion: Siderite is not an ore of silver.

4. **Analyze Option C: Ruby Silver**:
- Ruby Silver is another name for a silver ore, and its formula is 3Ag2S·Sb2S2, which indicates the presence of silver.
- Conclusion: Ruby Silver is an ore of silver.

5. **Final Conclusion**:
- Based on the analysis, the only option that does not contain silver is **Option B: Siderite**.

### Answer:
The option that is not a silver ore is **Siderite**.

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