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Posted August 30, 2005 7:00 AM

The question as it appears in the 08/30 edition of Specs & Techs from GlobalSpec:

Part of the beauty of ice sculptures is the ice is as clear as water. How is the ice made so there is no cloudiness?

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Anonymous Poster
#1

08/30/2005 11:17 AM

Or is it a temperature thing?

Commentator

Join Date: Apr 2005
Posts: 55
#2

Air and Gases Removed

08/30/2005 11:41 AM

The cloudiness is probably caused by air or gas trapped in the water as it freezes. If the air or gas is removed the result would be a crystal clear block of ice with no cracks or imperfections.

Active Contributor

Join Date: Jul 2005
Posts: 24
#6

Re:Air and Gases Removed

08/31/2005 10:52 AM

Would boiling the water firrst help remove any impurities, thus making the ice clearer?

Power-User

Join Date: Jun 2005
Posts: 104
#3

slowly... but surely

08/30/2005 12:34 PM

the simplest way is to freeze water very slowly, from a single cold point. It would be a single crystal, not unlike silicon wafer manufacturing. The other way is to freeze water not at the surface where it mates with air, but at the bottom of a bin or container, there would be no (or less) air to be trapped in the amorphous (many crystal) structure created.

Associate

Join Date: Aug 2005
Posts: 33
#4

Not that complicated

08/30/2005 12:57 PM

The most important thing to making crystal clear ice is to start with crystal clear water. Obviously, pure water will be much clearer than tep water when frozen due to the fact there are no particles suspended in it. Also, to help insure that equal clarity is achieved, the water is constantly circulated throughout the long freezing process. This forces all the water to be the same temperature when it freezes. It will then freeze as one solid, rather than lots of "chunks" frozen together.

Active Contributor

Join Date: Aug 2005
Posts: 16
#5

Ice Casting

08/31/2005 8:25 AM

My guess would be the process is similar to the continuous casting process used in steel mills.

A form the shape of the desired cross section is made with a temporary bottom. The lower section of the cast has the quick freeze plumbing attached. The water freezes from the bottom to the top, allowing the disolved gases to rise into the liquid. As the block depth grows, the form bottom is slowly lowered.

This way, custom blocks can easily be cut off of the crystal, and the ice should remain clear.

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Join Date: Dec 2004
Posts: 1995
#7

09/06/2005 12:27 PM

As written in the 9/06 issue of Specs & Techs from GlobalSpec:

The first step in making clear ice is to start with distilled or deionized water (to be sure the water is free of particles). Then boil the water to eliminate any air or other dissolved gasses in the water. The final (and most important step) is to freeze the water in layers rather than all at once — this approach avoids entrapping any bubbles (as air tends to get back into boiled water fairly quickly). When making clear ice, try to mimic the way icicles are formed in the winter — pure water (melted snow) drips down the icicle and freezes in layers.

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