Amber Properties

Based on “Właściwości bursztynu bałtyckiego” by Gabriela Gierłowska

Baltic amber (succinite) is a fossilized resin, formed over 45 million years ago. It is a “living” material constantly undergoing oxidation and polymerization processes. It was a very well known material to our ancestors who started to use it in XIII century BC. One of the oldest drawings of wild horses made in amber found in Meindorf (Germany) and Siedlice (Poland) are dated back to that time. Amber has been used by humans for several thousand years in arts, crafts and medicine. Today amber is mainly used in jewelry production, and its beautiful pieces can be found on international markets.

• Low density of amber (0.96-1.096 g/cc) makes it fairly light material, widely used for production of various jewelry pieces, including pendants, necklaces, earrings, bracelets or brooches.
• Amber contains 3-8% of succinic acid, which is believed to form from microorganism-induced fermentation of the cellulose contained in the resin. Succinic acid is believed to have health beneficial properties and was widely used in medicine.
• Amber flows in salt water whiles it will sink in fresh water. Centuries ago it was believed to have magical properties because of its ability to flow on surface of waves. Nowadays the same phenomenon can be observed on Baltic and North Sea during cold months, when water temperature is around 39F (4°C) and its density is at peak.
• Largest amber deposits can be found in Gulf of Gdansk (Poland), Sambia (Russia), Hel (Poland), Lubelski region (Poland), Polesie Wolynkie region (Poland) or Bitterfeld (Germany). It is deposited between 5 to 150 meters deep.
• Raw amber is found in different forms, sizes, shapes and colors which represent its genesis and formation. Its colors vary from white through red, yellow, orange to green and almost black. In general amber types can be divided in Primary and Secondary groups.
• Many pieces contain organic inclusions like: insects, arachnids, myriapods, small amphibians, plant remains, grains of sand and gas bubbles. Those inclusions are a source of knowledge for scientist researching on prehistoric organisms and animals.
  

  One of the most unique inclusions found in amber is “Gierlowska Lizard” trapped inside amber piece displayed in Amber Museum in Gdansk.

• Value of amber doesn’t depend only on its size, but also on its color, clarity, transparency and rarity. It usually feels warmer than other stones and is negatively charged, which is positive for human health.
• Amber is flammable. While burning it produces yellow light flame and pleasant resinous smell. Pliny wrote: “Pieces of amber, steeped in oil, burn with a more brilliant and more lasting flame than pith of flax.”
• One composition of an amber variety is: oxygenated hydrocarbon (carbon 61-81%, hydrogen 8.5-11%, oxygen 15%, sulfur 0.5%). It cannot be fully made into a solution. It partially dissolves in certain organic compounds: 20-15% in methanol, 18-23% in ether, 20.6% in chloroform, 21% in benzene, 25% in turpentine.
• Amber hardness on the Mohs scale varies from 2 to 3, while its microhardness ranges from 19.9 to 29 kg/mm2 .Hardness depends on its type, e.g: “bone amber” has a microhardness of 19.9 kg/mm2, transparent amber 26.2 kg/mm2, weathered amber 27 kg/mm2.
• Internal structure of amber varies from porous to solid. Porous structure is usually characterized by large number of gas bubbles which distribution influences the color and clarity of amber.
• Amber undergoes weathering process while buried in sediments and after excavation. In the past amber was kept in brine for protection. Nowadays synthetic waxes, resin reagents or gum turpentine are used for the same purpose.
• Prolonged light exposure causes damage to amber. In the first phase it will change its color to darker and lose its clarity and transparency. Its surface will become rough and in last phase cracks will appear and the top layer will start to peel off.
• Vacuum-heated distillation of amber will produce succinite acid, oil and colophony, which are used in medicine and as high-quality preservatives and lacquer ingredients.
• Amber boiled in vegetable oil will become very moldable. However, when rapidly heated will crack. Its softening temperature is 302F (150C) and melting point is 572F (300C).
• Natural substances like e.g. plant extract from Anchusa Tinctoria and well as synthetic dyes are used to dye amber.

Nowadays, amber used for jewelry manufacturing is very often “improved”. Raw material is placed in autoclaves where it undergoes certain chemical processes. As a result its clarity, transparency, color or hardness is changed. Also many pieces can be glued together or inclusions can be introduced. In XIX th century Spiller and Trebitsch patented methods for pressing amber. It is a process where tiny pieces or even amber powder is pressed under pressure and as a result a bigger piece is produced. Today’s technology allows manufacturers to produce pressed amber very similar to natural amber and distinction can be very difficult. Testing and identification of real amber can be difficult, since it is not very well soluble in any known solvents. Infrared spectroscopy is currently used validated method for amber testing.