Joseph Tanatar’s scientific legacy includes the so-called blowpipe method – a technique that has been used in the past for identifying unknown geological substances. Before the advent of modern spectrometers, the blowpipe method was a fundamental technique in field chemistry and has been part of the practical education in Freiberg for a long time.
In its simplest form, a blowpipe is a narrow tube made of brass or another metal, bent at one end and
terminating in a fine-pointed tip with a very small orifice.
When the pointed end of the blowpipe is placed just inside the flame of a lamp, candle, or a gas jet with
a narrow aperture, and a gentle stream of air is blown through the tube, the flame is deflected to one
side. It assumes the shape of a long, narrow cone, and its heating intensity increases significantly.
Many minerals, when held as a thin fragment in this directed flame, can be melted with relative ease; some
may even be partially or completely volatilized. In contrast, other minerals remain unchanged under the
same conditions.
Therefore, substances that appear similar can often be quickly distinguished from one another using the
blowpipe, making it a valuable tool for qualitative mineral analysis.
The blowpipe has three main applications in scientific practice. First, it is used to distinguish between
minerals based on their behavior in a flame, such as fusibility, color changes, magnetism, or
volatilization. Second, it helps determine the general composition of a mineral and detect the presence of
specific elements, including metals like copper, iron, or lead. Third, in some cases, it can be used to
estimate the amount of a known component in a sample.
The Method
In the blowpipe method, the flame of a candle, alcohol lamp, or gas burner is used for the thermal and chemical examination of minerals. Understanding the structure and chemical properties of the flame is essential for interpreting blowpipe reactions. The flame consists of several distinct zones.
When air is directed into the flame through a blowpipe, combustion becomes more intense and the flame is modified. The reducing and oxidizing zones become more sharply defined, their temperature rises,
and their chemical activity increases. Depending on the position of the mineral sample within the flame, the operator can produce either reducing or oxidizing conditions.
In blowpipe practice, these flame properties are used to:
- determine the fusibility of minerals
- observe oxidation reactions
- reduce oxides to lower oxidation states or to the metallic state
Such reactions are important diagnostic methods in classical mineralogical analysis.
Exploring the Freiberg Historical Collections
At 91²Ö¿âBAF, students in the project team studied the remaining historical instruments, samples, and artifacts.
Highlights from the Hands-on Experiments
Highlights from the hands-on experiments: At DniproTech, students gathered in the mineralogy lab to try out the blowpipe method for themselves.
