how do u cut a gem?

Answer 1

My freind works as an opal cutter,

The art and practice of gemstone cutting is known as lapidary. With consummate skill, the lapidarist can turn a rough mineral fragment or water worn pebble into a sparkling and valuable gem. The techniques used have been developed over many centuries and these skills, when combined with modern techniques allow gems to be cut to obtain the very best effects from each mineral's inherent attributes or special optical characteristics

Different cutting styles suit different gems. Transparent specimens like diamond are best faceted whilst the opaque gems, Agate, Onyx, Turquoise and Malachite are best cut as cabochons or as beads. The word Cabochon is a French word derived from the Latin 'cabo' meaning head or dome. Cabochons are the oldest and simplest way of cutting gems and the technique is still popular to this day.

Larger pieces of gem material such as Jade are often carved, though it would be more correct to say ground, into figurines, animals, bowls, vases and other artistic forms. The faceting of gemstones was developed much later than carving and did not become commonplace until mediaeval times.

The techniques were honed to their full potential during the last century.

Today, we understand more about the physical and optical properties of gems and are able to measure the properties and how light is affected by them. The modern lapidary with this knowledge and the use of very sophisticated and accurate machines can cut more beautiful gems than ever before. The gem is worked into a pattern of highly polished flat planes or surfaces which we call facets and which act as mirrors. Some light reflects from the top crown facets and displays the gem's lustre. Light also enters the gem through the crown facets and this is reflected off the bottom pavilion facets to re-emerge through the crown.

WHICH STONES WILL POLISH?

Most stones on the beach will not polish, but there are many that will. The harder stones polish best - those that look almost shiny already. Reject those stones which look grainy, they may be hard, but will not polish.

One way of checking the hardness of a stone is to try to scratch it with a penknife. If the knife cuts a mark or produces a powdery line, then the stone will not polish. If the knife leaves a metallic line, then the stone is harder than steel and it will polish. This is not to say that softer stones, such as serpentine, cannot be polished, but they must only be polished with other stones of similar hardness and not mixed with harder stones.

Tumbling times will be shorter with softer stones and a close watch will have to be kept on them, as it will not take so long to grind and polish them. Select stones that are generally 1 inch in diameter or smaller, one or two larger stones may be polished in a load that consists primarily of smaller stones.

GENERAL INSTRUCTIONS

STEP 1

Open the barrel by pushing either end cap off with your thumbs. When new they are sometimes tight, but if you immerse the barrel in hot water they can be easily removed. Squeezing one side of the barrel assists when opening. If you use warm water to fill the barrel it will help to suck on the lid.

Fill barrel ¾ full with stones and shake to settle. Do not use less, it will not work as there is no tumbling action unless the barrel is filled sufficiently.
Add water to just over the top of the stones.
Add 1 heaped tablespoon of coarse silicon carbide 80grit for a 1 ½ lb barrel or 2 heaped tablespoons for a 3lb barrel and 3 heaped tablespoons for a 5 lb barrel.
Run the machine for a few days and nights while occasionally examining the stones. Fairly smooth pebbles might need only about 3 days to become nicely rounded while very jagged ones may need 10 or more days running and the grit topping up to get the same effect. 7 days is a reasonable average.
When satisfied proceed to:-

STEP 2

Thoroughly clean the stones and barrel by removing both ends.
Proceed as before using 220 grit this time .It should only be necessary to run this grade for about 5-6 days .
STEP 3

Thoroughly clean stones and barrel by removing both end caps, washing carefully.
Proceed as before using the same proportions of grit and water but this time use 400 grit. Please note this stage is very significant and determines the final polish, it is vital you do not cut it short.
Allow at least 7 days tumbling. Do not top up with fresh grit as this will re roughen the stones .Each day on this stage imparts a smoother finish as the grit breaks down and progressively smoothes the stones making it far simpler for the next stage
STEP 4

Very, very thoroughly clean the stones and barrel. It would be useful to keep one barrel to be used specifically for polishing only, because of the difficulty of cleaning grits completely from the sides of the barrel .Additional barrels may be purchased separately .Examine the stones very carefully and make sure that they are very smooth. Discard any stones that are badly cracked or have jagged edges- they can be re tumbled with your next load.
Repeat steps as before using similar amounts of water but one level tablespoon of cerium oxide instead of grit for a 1 ½ lb barrel (adjust amounts accordingly for the size of barrel as with the grits). If the barrel has been cleaned out properly and the previous steps are carried out correctly 7 days running should produce gleaming stones! Remember as with all things practise makes perfect.
Do not put any of the resulting slurry down the sink - it is inclined to set solid!


Hope this info helps you.

Answer 2

my dad cuts gems as a hobby. you buy or rent a lapidary machine. and buy discs with diamond dust in it. then figure out the best way to cut the stone and make it shine nicely. then attach the rock to the machine with wax and grind away using smaller grains coarsenesses until it's completely smooth and voila. a gem. it takes a lot of planning an stuff. for a beginner, i suggest cutting marbles. they turn our really cool actually.

Answer 3

Try the "Lapidary Journal"site it will give u some info.

Answer 4

with a gem knife

Answer 5

with high energy laser light

Answer 6

with diamond