Knowledge Base › Troubleshooting Atlas › Floatation & mounting
Mounting medium fails to clear (cloudy mount)
Also known as: cloudy mount, unclear mount
What it looks like
The mounting medium appears hazy or opaque instead of clear, obscuring details of the tissue.
Where it usually appears: Usually appears after the application of the mounting medium during the slide preparation process.
Likely causes
- Inadequate clearing of the tissue before mounting
- Contaminated mounting medium
- Improper mixing of the mounting medium
- Old or expired mounting medium
Immediate checks
- Inspect the mounting medium for cloudiness or particulates
- Verify the clearing agent used prior to mounting
- Check the expiration date of the mounting medium
Corrective action
- Reapply a fresh layer of clear mounting medium
- Use a new batch of mounting medium
- Ensure proper clearing of the tissue before remounting
Preventive action
- Store mounting medium as per manufacturer's recommendations
- Regularly check and replace expired reagents
- Implement a quality control process for reagents
This atlas is for educational purposes for laboratory professionals. It does not replace your institutional SOPs, manufacturer instructions, validated protocols or pathologist judgment. Adapt any action to your laboratory and equipment.
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