Amber pressed

At one time the small fragments of amber produced during the fabrication and machining operations were used to produce varnishes. In 1880 they were first used in the production of Ambroid. This is made by pressing the fragments in a hydraulic press at temperatures somewhat above 160°C. The moulded product has a close resemblance to amber. A form of extrusion has also been used to produce amber rods for subsequent conversion into pipe and cigarette-holder mouthpieces. 

Serpico, M. and R. White (2000a), Resins, amber and bitumen, in Nicholson, P. T. and I. Shaw (eds.), Ancient Egyptian Materials and Technology, Cambridge Univ. Press, Cambridge, UK, pp. 430-474. 

Figure 1.30 Pressed amber, showing oxidised oudines of amber pieces.

Figure 1.31 Ambroid pressed amber, showing feathering .

Figure 1.32 Old pressed amber beads (Victorian), and heat-treated Baltic amber beads (modern).

Figure 1.33 Detail of old pressed amber beads, showing surface deterioration.

Fuzzy, blurred lumps of darker colour in a pale matrix indicate pressed amber (Fig. 1.30). 

Lines of opaque and clear material and feathered swirls indicate pressed amber ( ambroid ) (Fig. 1.31). 

Surface crazing that is clear, on items of amber jewellery of even colour - either transparent or opaque - could indicate pressed amber from the end of the nineteenth century. Typical examples are beads, or brooches with a motif of flowers or fruits in clear material, on an opaque background (Fig. 1.33). 

Ultraviolet lig t. Most amber and copal fluoresces in UV lig t (Figs 1.13 and 1.16). This fluorescence dims if the amber has been treated with heat to clarify it or to press it. It also tends to dim and change colour with age - fleshly cut or polished amber will alwa3rs fluoresce more strongly. 

The late nineteenth century saw the appearance of pressed amber, which was popular for smoking requisites and jewellety. Favourites pieces were faceted beads and brooches depicting flowers and finiit. Early plastics also appeared on the maricet and pretty, red Bakdite beads imitated burmite. When the film Jurassic Park came out at the end of the last century natural amber saw a renaissance, and it remains popular today. 

Bakelite keeps well and does not degrade in the same way as other early plastics, thou it can de. Today it is still in production, and though its uses are limited, it is ain gaining popularity. Early Bakelite items are collectors items, and - to illustrate the change in values - there have recently been reports of dyed pressed amber being sold as Bakehte. 

Pressed reconstituted amber - ambroid Elongated, feathered swirls None Chips Floats Faint chalky- blue Faintly resinous... 

Poinar, George O. (1992). Life in Amber. Stanford University Press. 

Sesame oil from roasted sesame seed has the characteristic flavor and color of the roasted sesame oil the filtered crude oil is used without further refining. Sesame oil from cold-pressed unroasted sesame seed is also used directly after filtration as a flavored oil. Crude sesame oil from unroasted sesame seeds after screw-press or hydraulic press or solvent extraction, which varies in color from yellow to dark amber, may need further refining. Refined sesame oil is usually pale yellow in color. 

Properties Pale-amber liquid. Mw 210.21, mp (decomposes above 100C), vap press <1 mm Hg (20C). 

Properties Dark amber liquid ammonia-like odor. D 1.0812 (20C), bp 244C (50 mm Hg), flash p 370F (187C) (OC), vap press less than 0.01 mm Hg (20C), sets to glass at —7C. Moderately soluble in water. Combustible. 

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