There are fancy, expensive molds available which are meant to create clear ice suitable for adding to a glass of whiskey. Reviews suggest some work better than others. But why fork out your hard-earned cash for something you can easily make yourself using an empty beverage can and an extra thick stubby holder or with some bubble wrap.

The way to create clear ice is to use 'Directional freezing'. Normally an ice cube will freeze from all sides, inwards. This traps air and any impurities into the center of the ice cube and causes it to look a bit cloudy. With 'Directional freezing' the container is insulated all around except at the top. This way the water freezes from the top downwards. The impurities are forced downwards. The ice is removed from the mold when the bottom is not quite yet frozen. The impurities should still be in the remaining water. If the bottom has frozen a bit, just chip the cloudy ice away. The ice above will be nice and clear. Using a beverage can results in a round disk of ice being created, about the same size as an ice hockey puck which fits nicely into the whisky glass, bit like placing a round peg into a round hole.

Supplies

Empty beverage can
Extra thick Stuby holder or Bubble wrap

Step 1: Creating the Mould

A mold for the clear ice is made by cutting the top off an aluminum beverage can using a knife and trimmed with a pair of scissors.

Step 2: Using a Stubby Holder

Place the mold into a thick stubby holder, (the thin ones don't really work so well).
pour in a cup of water
Freeze for about 7 hours

Step 3: Removing the Unfrozen Bit

After about 7 hours, remove from the freezer and turn the mold and stubby holder upside down on a bench. After a while the ice ingot will slide out. Use a bread knife to chop away any partly formed ice on the bottom. Place the ice on a heated tray as an easy way to get a smooth surface where the ice was chipped away.

Step 4: Clear Ice

As ice and ethanol (alcohol) have similar index of refraction, when whisky has been added to a glass with clear 'ice hockey puck' shaped piece of ice, it looks almost invisible. It almost appears like you have a half full glass of whisky.

Step 5: Using Bubble Wrap

I found creating insulation around the beverage can mold using bubble wrap works really well. Wrap about 4 layers of bubble wrap around the outside and underneath. Secure with tape. Pour in a cup of water and freeze for about 8 hours.

Step 6: Storing the Clear Ice Pucks

If you don't want to use the ice immediately, Store the clear ice in a sealed plastic bag in your freezer until needed.

Step 7: Using a 5 Litre Container

If you want to create a larger block of ice, no worries, just use a larger container, say a 5 liter tub, wrap the sides and bottom with multiple layers of bubble wrap (more the better) fill up with water and place into the freezer for about 19 hours, after this time, the top 2 inches will have frozen but the bottom won't have.

Step 8: Making Ice Blocks

Once the tub has been taken out of the freezer, let the ice temper for about half an hour. Then using a bread knife, create a series of groves on the top. Hit the top of the knife with a mallet if available on a groove. This should break off a strip of clear ice.

Step 9: Shaping the Ice

Then break the strip into cubes. These cubes can be shaped on a warm surface. Place the finished wet blocks into a tray, not touching each other and dry them by placing the container into a freezer for 15 minutes. Finally, place the finished ice blocks into a plastic bag an into a freezer until they are ready to be used.

Step 10: Bigger Block

A bigger block can be created by not cutting it up. Maybe this could be used for ice carving of shaped into a lens and used as a magnifying glass to focus the sun's rays into starting a fire.

Step 11: But Wait, There's More

Clear ice is great, but it can be better. There seems to be a crazy for spherical ice blocks and these can be crafted by hand or made in an expensive mold. But wait, beer can technology has an inexpensive solution. Create 'flying saucer' shaped ice using a couple of humble beer cans. This time the cans need to be full as it makes them better at shaping ice. And how is it done? - just look at the photos.

Step 12: Storing Clear Ice

Store the clear ice cubes in a plastic bag in the freezer. Before using them in a drink allow them to 'temper' for 15 to 30 minutes and this will allow them to become clear again.