What is the impure form of zinc commonly known as ?

Explanation

To answer the question "What is the impure form of zinc commonly known as?", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the name of the impure form of zinc. Impure forms of elements often contain other metals or substances mixed with them.

2. **Identifying Impure Forms of Zinc**: In the case of zinc, one of the commonly known impure forms is an alloy. Alloys are mixtures of two or more metals.

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