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I'm currently looking at a French fob watch, and I've noticed what I can only describe as a 'cloudy' part of the crystal, as seen in the pic.

I've tried buffing this off with Windowlene, and then with (gasp!) acetone, but neither of these seems to have made an improvement.

This situation is new to me, I've not seen anything like this before. Am I in for a replacement crystal or how can I remove this, please? - I'm not really sure that this is something that is going to buff out as it doesn't exactly look like a a scratch and the area is not centred on the crystal?  ...

TIA

Ian

 

cloudy crystal.jpg

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It almost looks like it has been stained. It depends how deep this is. Some on here have had success in polishing out scratches. However I am not a patient person so unless imperfections are minor I just change the crystal. 

 

 

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I use Simichrome which does a good job, just make sure the imperfection is on the outside, I spent ages the other day trying to polish out a blemish like yours only to find it was on the inside of the crystal, no idea how it got there though.

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I use Abenaqui scouring paste (for kitchen cleaning) on a papertowel.  If it's a deep imperfection, a bit of very fine wet or dry paper speeds it all up.

Shane

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If that is a glass crystal, then the crystal is probably "etched". A sticker or or something else that was slightly acidic was sitting against it for a long time, perhaps?

The way to get rid of that on a glass crystal is to polish with cerium oxide, I've seen a suggestion of using a piece of dowel rod to hold the cerium oxide paste (at the end). Supposedly makes it easier to handle than using a cloth. 

 

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2 hours ago, dadistic said:

The way to get rid of that on a glass crystal is to polish with cerium oxide, I've seen a suggestion of using a piece of dowel rod to hold the cerium oxide paste (at the end). Supposedly makes it easier to handle than using a cloth. 

Abenaqui scouring paste (I'm sure there is something similar in your location) uses feldspar which has a Mohs Hardness of 6 and works quite well on glass (if you are patient) and plastic crystals.  Glass has a Mohs Hardness number from 5.5 to 7, depending on the glass.  Cerium oxide was listed on the chart I found at 7, which will work faster but is more expensive and less available were I am.

I have used the piece of wood trick before but not on crystals (should still work).  The abrasive gets embedded into the wood and continues to cut rather than getting lost somewhere in the cloth.  Just make sure you average all of your polishing out across the crystal, otherwise you will see waviness through the glass.

Good luck.

Shane

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4 hours ago, watchweasol said:

Hi There are propriatry  (polywatch)pastes for polishing watch crystals but I use Automotive chrome cleaner (Autosolvol) its mild enough and polishes ok takes a bit of elbo grease as does any polishing.

I also use autosol. It was mentioned in a de carle book. I Have tried other things as well, bicarbonate powder not as effective  and also eucryl toothpowder which does actually work ok. But the Autosol is by far the best and is very comparable to polywatch, in fact i couldnt tell the difference.  I start with 600 grade wet and dry depending on how deep the scratches then 200 grit increments up to 2000 and then finish with Autosol. A crystal generally takes about 20 mins to half an hour depending how bad the scratches.

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