Spectroscope is used to identify the different elements that can
be present in minerals. Basically, it is an enhancement of the blowpipe
in the sense that it uses a heat source to fuse minerals. There
are many differences between the two apparatuses. First, the blowpipe
gives off an inconsistent rate of heat because a human’s breath
is by no means constant. The spectroscope gives off a constant rate
of heat, via the arc-flame between the carbon rods, so the results
will have a smaller margin of error. A second difference is the
heat index. The hottest part of a blowpipe flame has been known
to reach about 1500°
C. The spectroscope has a heat index that can range from about 2000° C to an intense heat of about 3000°
C. This is very helpful because it causes the mineral to fuse faster,
which in turn gives us better and quicker results. Also, the samples
that are used in a Spectroscope are crushed into very small particles,
this creates more surface area for the heat to interact with the
mineral therefore causing the rate of fusion to increase. It would
be hard to use crushed minerals with a blowpipe because you would
just blow the sample away (blowing hot particles of rock is a major
What it does:
light is composed of light of all colors of the visible spectrum.
These colors differ from one another in wavelength. A spectroscope
is an instrument, which separates these different wavelengths,
or disperses them into a spectrum for visible observation. Different
elements have different flame colors. The Spectroscope analyzes
these colors by identifying the wavelengths producing them. In
many cases color is found from the combination of several wavelengths.
When atoms are heated their electrons are excited and rise to
higher energy levels; the higher the temperature, the higher the
state of excitement. When the electrons fall to lower energy levels
the emission of radiant energy occurs. The energy difference between
the two levels determines the wavelength of the emitted radiation.
Since the electronic configuration of the atom is different for
each element, every element has a characteristic spectrum.
Before even touching the Spectroscope, you should
be aware of all dangers present in the device as well as the ways
to safely avoid these dangers. This section tries to provide an
exhaustive list of cautions, but is still liable to human error.
Use your head and keep watch for dangers not described in this
- Do not touch the arc.
Temperatures between 2000° C and 3000° C mean severe burns, you may even
catch on fire.
- Do not look at the arc.
The intense light will damage your eyes, just like looking at
the sun. There is a mylar window on the right side of the chimney
that will allow you to see the arc-flame without danger.
- Do not touch the carbon rods or
anything near them after use. Surfaces near the carbon rods will
stay hot enough to severely burn you even after turning off
the power supply.
- Do not touch the glowing cones.
These are parts of the power supply located just to the left
of the viewing mechanism on the base of the Spectroscope under
a protective guard. During and after operation the cones and
the protective guard will both be hot enough to burn.
- Do not look down chimney during
operation. Not only might harmful gasses be evolving from the
burning sample, but also poorly crushed bits of sample might
shoot up and into your eyes.
Personal Protective Equipment:
Eyes: Welder’s (mylar) goggles for looking
into the flame. Safety glasses for general operation.
||Skin: Use tweezers or tongs to place/remove
anything from the staging area.
|| Inhalation: Always use the Spectroscope in
a functional and operating fume hood. Some samples may evolve
dangerous and/or stinky gasses.
a rock or mineral you would like to analyze for elemental contents.
Then crush them with a mortar and pestal until it is a fine
powder. Then lead a heaping quarter-teaspoon onto the tiny specimen
sure the power is off when coming anywhere near the electrodes.
Put sample feeder all the way down and electrodes at least an
inch apart. This makes placing the sample on the specimen hearth
carbon rods together so that they are touching, make sure that
their tangent point is directly above the center of the sample
so when you feed the sample it is consumed directly in the electric
current. Also with the rods centered, the light of the combustion
is aligned perfectly with the Spectroscope’s optics.
sample awning up to protect from harmful light and heat emission.
with the carbon feed knob until you get an electric arc between
rods, once this happens look into the welders glass only and
separate rods to about 1/8th of an inch apart. This
distance creates a good heat index.
looking through welder’s glasses slowly feed the sample up into
the arc until you see the sample start to melt, or you see the
arc-flame change its character.
the Spectrum films. There are a number of films one can use.
There is one for each major terrestrial element. It would be
a pain to check each against the short-lived sample so we recommend
using film 20 on the right side as it allows quick identification
of many elements.
matter what film you use, it has a set of Sodium-D reference
lines (they appear as strong double lines). Sodium always shows
as it is in the electrodes. Looking through the eyepiece, align
the double Sodium-D lines with those in the center spectrum
of the Spectroscope.
into the eyepiece and slowly move the up and down without adjusting
any of the film knobs. There should be bright horizontal lines
connecting the two element films, these lines are indicators
of the prominence of the element that they light up, the brighter
the line, the more of the element in the mineral.
using the heat increase knob, this may brighten the lines and
make them easier to see. Our suggestion is that you try both
and not just one.
your results. If you didn’t have enough time to get a good look
at the whole spectrum, try it again! It doesn’t take too long
and you don’t need much rock to make many samples.
Exciting Spectroscope Links:
Spectrex, the maker of the Vreeland Spectroscope
inspired by the Spectroscope:
Burn my crush rock samples, burn
Many colored flame
Who are you rock friend?
Secrets now known by glowing
Rods of ‘lectric truth
Old arc jump
Project due too soon