Editing Amber (section)

===Treatment===
The Vienna amber factories, which use pale amber to manufacture pipes and other smoking tools, turn it on a [[lathe]] and polish it with whitening and water or with [[rotten stone]] and oil. The final luster is given by polishing with flannel.{{sfn|Rudler|1911|p=793}}

When gradually heated in an oil bath, amber "becomes soft and flexible. Two pieces of amber may be united by smearing the surfaces with linseed oil, heating them, and then pressing them together while hot. Cloudy amber may be clarified in an oil bath, as the oil fills the numerous pores that cause the turbidity. Small fragments, formerly thrown away or used only for varnish are now used on a large scale in the formation of "ambroid" or "pressed amber".{{sfn|Rudler|1911|p=793}} The pieces are carefully heated with exclusion of air and then compressed into a uniform mass by intense hydraulic pressure, the softened amber being forced through holes in a metal plate. The product is extensively used for the production of cheap jewelry and articles for smoking. This pressed amber yields brilliant interference colors in polarized light."<ref>{{Cite book |last=Project Gutenberg |url=https://books.google.com/books?id=oil4DgAAQBAJ&pg=PT2383 |title=The Project Gutenberg Encyclopedia |date = January 2021|publisher=Prabhat Prakashan}}</ref>

Amber has often been imitated by other resins like [[copal]] and [[kauri gum]], as well as by [[celluloid]] and even glass. Baltic amber is sometimes colored artificially but also called "true amber".{{sfn|Rudler|1911|p=793}}