In order to melt metals such as gold and silver, goldsmiths blow the outermost zone of a flame towards the gold or silver using a metallic blow-pipe.
Why is the outermost zone of the flame blown towards the gold or silver?

Explanation

To understand why goldsmiths blow the outermost zone of a flame towards metals like gold and silver, we can break down the explanation into several steps:

### Step 1: Understanding Flame Zones
A flame consists of different zones, each with distinct characteristics. The outermost zone of the flame is known as the outer envelope or outer cone.

### Step 2: Characteristics of the Outermost Zone
The outermost zone of the flame is where complete combustion occurs. This means that there is a sufficient supply of oxygen, allowing the fuel to burn completely.

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