Some of the very old glass objects appear slightly milky instead of being transparent. Why ?

Explanation

**Step-by-Step Solution:**

1. **Understanding Glass Composition:**
- Glass is primarily made up of silica (SiO₂). It exists in both crystalline and amorphous forms.

2. **Nature of Glass:**
- Glass is an amorphous solid, meaning it lacks a long-range order in its atomic structure. However, it can have some degree of crystallinity.

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