A good paraffin for routine use has a melting point of:

• A. 40-45 C
• B. 55-58 C
• C. 65-70 C
• D. 75-80 C

Answer: (B)

The key idea is matching the paraffin’s melting point to how it will be handled during processing and microtomy. A mid-range melting point around 55–58°C gives a paraffin that is solid enough at room temperature to support delicate tissue structures, yet soft enough to melt or soften in the warm embedding and mounting steps so sections can be released, flattened, and mounted with minimal artifacts. If the melting point is too low, the paraffin would be too soft during handling, leading to tissue distortion or tearing. If it’s too high, the paraffin becomes too hard, making infiltration and sectioning more difficult and increasing the risk of damage to the tissue. Therefore, 55–58°C is the most practical choice for routine use.