The physical properties of high-purity drugs can vary depending on the type and chemical structure, but some common properties include: 1. **Color**: High-purity drugs tend to be purer in color. For example, high-purity cocaine is usually white crystals, while high-purity heroin may be white or pale yellow powder. 2. **Texture**: Drugs with higher purity tend to have more consistent textures. For example, high-purity methamphetamine is generally transparent crystals, while low-purity ones may be powder or blocks. 3. **Smell**: Some high-purity drugs may have a characteristic smell. For example, high-purity MDMA may give off a synthetic-like smell, while low-purity ones may have a different smell due to the presence of adulterants. 4. **Gloss**: High-purity crystalline drugs may show a strong gloss under light, such as the glassy gloss on the surface of crystals of methamphetamine. 5. **Melting point**: Since impurities affect the melting point of a substance, high-purity items usually have a relatively fixed melting point. Testing their melting point is a way to test purity. 6. **Solubility**: Drugs with higher purity will dissolve more stably and quickly in specific solvents. It should be noted that although the above characteristics can be used as a reference for preliminary judgment of drug purity, accurate identification requires chemical analysis and professional testing equipment to determine purity and composition. Illegally manufactured and sold drugs carry huge risks and legal liabilities, and anyone should stay away from these substances.