|
Okay, someone please tell me
what happened to the month of September? October is
here and we'll be turning our clocks back October 30th @
2:00am. Did you know that the federal law that
established "daylight time" in this country does not
require any area to observe daylight saving time? But if
a state chooses to observe DST, it must follow the
starting and ending dates set by the law. From 1986 to
2006 this has been the first Sunday in April to the last
Sunday in October, but starting in 2007, it will be
observed from the second Sunday in March to the
first Sunday in November, adding about a month to
daylight saving time. With October here
it's time to for us to get busy with some fall jewelry
making and to start thinking about Christmas.
Here's a question from one of last month's
subscribers.
Question: How are rough
diamonds cut & polished
if diamonds are the hardest material
on earth?
Answer: Since we see the results every day in jewelry stores,
we know that rough diamonds can be cut, however
they can only be cut and polished by using other
diamonds -- usually in the form of diamond dust.
The rough diamond in the photo below is an excellent
specimen of an octahedral crystal, the most common of
the many shapes of rough diamond. This is called the
habit of
diamond crystal. If you care to see an uncut
octahedral diamond (right from mother nature), just ask
Sylvia or Tim next time you're in our store. We
purchased one several years ago and would love to show
it to you.
The sketch in the center shows how diamonds were cut prior to
the invention of the diamond saw in the twentieth century. The
rough diamond was cleaved in two identical pieces
resulting in diamonds cut to retain maximum carat
weight and not ideal sparkle proportions. For example,
this may yield two diamonds of around 3/4th carat.
The sketch on the right shows how we cut diamonds
today with the invention of the diamond saw. We can now
cut diamonds with well-cut proportions. For example this
may yield a larger diamond of 1 carat and a smaller
diamond of 0.5 carat.
 
When such a crystal is fashioned into a
brilliant gemstone, the diamond cutter takes the
stone through many detailed steps, the most important of
which are:
Cleaving When a rough diamond is determined
to be suitable, it is carefully studied for every detail
of its structure. It will then be marked and given a
sharp blow with a special hammer to separate the stone
into two carefully planned parts. This is a risky
undertaking, and only used in rare cases since the
advances in mechanical cutting devices allow even the
most difficult stones to be cut with little
attention.
Cutting In most cases, a diamond will be
cut with a saw blade. Since diamonds are the hardest
material known (which means they cannot be scratched
with any other substance), only diamonds can cut
diamonds. So the diamond is securely mounted and held
against a thin alloy blade impregnated with diamond dust
and covered with linseed oil. As the blade turns, it
carries small particles of new diamond dust which sticks
to the oil and continues the process until the entire
diamond is split in two. This can take several days for
a diamond over 1 carat or more.
Bruting After a diamond is the height and
width desired, it is crudely shaped into the round or
other shape by rubbing it against another diamond on a
high-speed lathe specially designed for the purpose. The
bruter takes the rough from an octahedral shape to a
more rounded shape in the case of many round brilliant
diamonds.
Faceting Then the long and precise process
begins to create the many facets that you have seen on
diamonds in stores. Each facet is created by grinding
the diamond on a horizontal blade as it spins with
diamond dust and linseed oil, similar to the cutting
blade.
First, the large facet at the top is
ground until level and smooth. Then the major facets are
created on the bottom (called the pavilion), followed by
the large facets on top (called the crown). Then the
pavilion facets are refined into more facets, followed
by the crown facets. The final touch is often the tiny
flat facet at the point of the pavilion, called the
culet.
The finished round brilliant diamond, for
instance, will have 58 facets, including the tiny culet
and large table facets.
Each step in this delicate process is generally
carried out by a specialist who spends many years in
apprenticeship to accumulate the great skill required.
Every tiny mistake can risk a gem worth thousands of
dollars. Only experience can safeguard nature's
treasures and bring out the true beauty of a
diamond.
___________________________________________________________
Don't know their size?
Don't know their taste?
Then give the Prospector gift that's
sure to Please:

Our New Gift Card is perfect for
birthdays, anniversaries, holidays or "just because".
It's available in any denomination you choose and
redeemable for merchandise online or in our store. Call
or email us today to order a gift card for that
special person in your life.
It you have an
idea for future articles or want me to provide research
on a certain topic, please email me with your
suggestions. Please type “Article Idea” in the subject
line.
Call (814-793-4479) us or email today for any requests and experience
The Prospector Difference. |