Category Archives: General

 Areas of use for glass

Nowadays, glass is an inseparable part of our daily lives. Besides being used as glass balls and borosilicate glass, there are many areas where glass as a material can be used. For example, about 40% of all beverages are „packaged“ in glass.

Through decades of experience, knowhow and the continuous development of our production techniques in the manufacture of our small borosilicate glass balls, Schäfer Glas has earned a good reputation worldwide. Our customers appreciate our good service and the high quality of our products. The production of these small borosilicate glass balls starting from a size of 1 mm, requires partly, in this case, a process of several extensive production steps

At the glassworks, the secondary raw material is melted down and used, amongst other things, for the production of new glass packaging and containers. Afterwards, the Recycling symbol – which comprises 3 arrows – and which reflects the recycling program used. For the three we’ve already discussed, we have the following Recycling codes for different colours of glass– 70 GL for colourless, 71 GL for green and 72 GL for brown glass.

Glass recycling is the collection and recycling of used glass and is considered as the archetype of the modern recycling economy. The collection, processing and recycling of waste glass has been prevalent since the seventies in Germany.

Collection in used glass recycling containers

Initially, used glass is collected in the so-called used glass recycling containers in the bring-it-yourself system. As a rule of thumb in Germany, it is separated according to colours: white, green and brown. Special colourations such as blue or red glass are allocated to the green glass section. A strict colour separation is important for the subsequent recycling process. Small quantities of coloured glass cause an unwanted coloration in the white glass melting process and can vice versa lead to a lot of white glass with regards to the decolourization of coloured glass. Such products may then no longer be used, which is why particular attention to the correct separation is paid.

By the nature of Genesis

In general you can divide glass into two groups: natural glass and artificial glass. While artificial glass is produced by the melting of several raw materials, natural glass is produced by processes in nature. The best known of such processes has to be the formation of obsidian and pumice. These natural types of glass result from volcanic eruptions of lava. Even a few millennia ago such natural glass was being used by humans for various purposes. Other natural glasses include tektites (meteorite impact) and fulgurites (lightning impact).

By the nature of „chemistry“

The components of glass

Glass is a high-quality, extraordinary and versatile material that possesses amazing properties. 

Glass is a material comprised of natural and nature-identical raw materials. Various substances such as soda (sodium carbonate), potash (potassium carbonate), limestone (calcium carbonate) and boron oxides are added to the main component of quartz sand (silicon dioxide). Silica, sodium oxide and calcium oxide are necessary for solidification and melting, as well as for corrosion protection.

Crystal balls and Occultism  (= the study of hidden things, Secret Sciences) are two concepts that arewith each other formany centuries. As traditional requisite for Occultism crystal balls among other things have long been used for clairvoyance. While there is no scientific basis for the view of events the fascination of the mysterious crystal balls is unbroken.

So it should work best

Full moon is  supposedly the best time for clairvoyance. Run lukewarm water on the crystal ball for 3 minutes (for cleansing) and then expose it to the full moon irradiation the whole night. According to the clairvoyant, it is possible to achieve the clearest and best result.

History of Glass Grinding

Glass grinding at Schäfer Glas

First horizontal Grinding benches were used already in the 7th Century BC for processing Glass type objects. The objects found during excavation were partially traces of ground rings.When a work piece is chucked in a lathe-type device or clamped on a turntable and a wood is centered, a pattern develops accordingly. Always two persons were required for processing as per this method.One persons works on the work piece with the tool,and the other turns a type of crank. At first such glass pieces were discovered during excavations from Mesopotamia so far. It is believed that this handicraft had spread from there to Mediterranean.

Glass has been used for many centuries in the production of fashion jewellery. Fashion jewellery is – as the word suggests – jewellery that matches the latest fashion trends and unlike real jewellery is much cheaper. The earliest form of fashion jewellery was in ancient Egypt in the style of reconstituted beads. Fashion jewellery is also known by other terms: Rhinestones and rhinestone jewellery can also be classed as fashion jewellery.

Reflectors in traffic engineering

We encounter reflectors in many different ways in our daily lives, including in the important traffic engineering sector. Retroreflectors are safety devices which, particularly in the dark, reflect incident light back to the light source. The special optical, chemical and mechanical properties of glass ensure that this material finds many uses in the challenging traffic engineering sector. Its hardness and heat resistance are enough to ensure that it is often preferred to plastics. 

Requirements for good reflective properties