The name baryte is derived from the Greek word βαρύς (heavy). The American spelling is barite.
Baryte, or barite, is a mineral consisting of barium sulfate. The baryte group consists of baryte, celestine, anglesite and anhydrite and is the main source of barium. Baryte itself is generally white or colorless but the colour can vary with the presence of impurities. Its main properties are its high specific gravity (4.5) which is exceptional for a nonmetallic mineral, very low solubility; it is non-toxic, and also chemically and physically unreactive.
Baryte often occurs as concretions and void-filling crystals in sediments and sedimentary rocks. It is especially common as concretions and vein fillings in limestone and dolostone. Where these carbonate rock units have been heavily weathered, large accumulations of baryte are sometimes found at the soil-bedrock contact. Many of the commercial baryte mines produce from these residual deposits.
Baryte is also found as concretions in sand and sandstone. These concretions grow as baryte crystallizes within the interstitial spaces between sand grains. Sometimes crystals of barite grow into interesting shapes within the sand. These structures are known as "baryte roses". They can be up to several inches in length and incorporate large numbers of sand grains. Occasionally baryte is so abundant in a sandstone that it serves as the "cement" for the rock.
Baryte is a common mineral in hydrothermal veins and is a gangue mineral associated with sulphide ore veins. It is found in association with ores of antimony, cobalt, copper, lead, manganese and silver. In a few locations baryte is deposited as a sinter at hot springs.
The Baryte in the Barberton Greenstone Belt formed about 3.24 billion years ago. Dissolved barium seeping through faults and fissures in the shallows of the Archean ocean probably combined with sulphate from the atmosphere as a result of the sun's radiation. Just like salt crystals grow in salt water, blade like crystals of baryte slowly grew in the shallow bays of this sea, forming crystal lawns and growing into cauliflower-like masses. Over time , wave action broke off blades an ground them into fine grains which mixed with sand and buried the crystal masses.
Bands of baryte in this area lie between sandstones and mudstones and were once mined in shallow trenches.
Uses:
Some 77% worldwide is used as a weighting agent for drilling fluids in oil and gas exploration to suppress high formation pressures and prevent blow outs. Other uses are in added-value applications which include filler in paint and plastics, sound reduction in engine compartments, coat of automobile finishes for smoothness and corrosion resistance, friction products for automobiles and trucks, radiation-shielding cement, glass ceramics and medical applications.
To log this EarthCache you have to answer the following questions and e-mail the answers to me:
1. Take a look at the rocks in front of the information plate. How many rocks are there on display?
2. Describe any crystals that you can observe.
3. Name one of the crystal clusters shown on the panel.
Uploading photos to the cache page is the best way to say thank you to the cache developer and to encourage others to visit the location but is only optional.
NOTES:
- There are no other facilities along the trail except for very nice picnic spots.
- The distance is about 40km from Barberton on a narrow and winding road up to the Bulembu border post to Swaziland with no or limited cellphone reception.
- You can email me your answers in either Afrikaans or English.
Note that a handy guidebook specially compiled for this route is on offer at Barberton Tourism in town.
Enquiries: 013-712 2880 or www.barberton.co.za
Guided tours by Tony Ferrar on 072-376-2581 and Dave Mourant on 082-923-5366.
Thank you to the Barberton Chamber of Business and all those involved to develop this geotrail.
