White glass

Experiments were made with pure 2-propanol samples stored for six months in white glass containers, which were half full and exposed to the light. It could be proved that peroxides form in these conditions. The experiment showed that peroxidation is faster when a ketone is present. The fact that this oxidation only takes place with secondary alcohols shows that it affects the hydrogen atom in the a position of the active group, (atom that is more reactive than a primary hydrogen), and not the actual function. 

Hancock, R. G. V., Aufreiter, S., Kenyon, I., and Latta, M. (1999b). White glass beads from the Auger site, southern Ontario, Canada. Journal of Archaeological Science 26 907-912. 

Zinc sulfide (ZnS) is used as a pigment and to make white glass, rubber, and plastics. It is an ingredient in pesticides, luminous paints, and X-ray and television screens. 

Ail the varieties were of French manufacture. DTTTEH-EHT VARIETIES OP WHITE GLASS. ... 

Lime.—This substance, which forms an important constituent in flint-glass, maybe introduced either as a carbonate, or slaked or burned. Limestone, however, that contains proto-carbonate of iron, must be excluded from tha mixture for making white glass. The action of lima is to render the alkaline silicates insoluble, and when rightly balanced by the other ingredients, it promotes the fusion of the whole, and improves the quality, but when added in excess, the glass becomes hard and difficult to work, and subjoet to devitrification. 

II, White Bottle ok Chemical Glass.—Under this head may be included white glass for medicinal bottles and chemical purposes, refractory Bohemian glass for tubing, et cetera, and foreign crown. The most beautiful material for bottles is furnished by flint-glass or crystal, but these are only intended for ornamental articles Or vessels for the table, and will be alluded to under Flint-glass. 

Stir the mixture with a glass rod until solution is complete, allow the solution to stand for 15 min, unless otherwise directed, and compare the color of the solution with that of the specified matching fluid in a comparison container that also is of colorless glass and has the same internal and cross-section dimensions, viewing the fluids transversely against a background of white porcelain or white glass. 

In summary, the violet color (objects 5, 7, 8) is caused by iron in the presence of manganese and cobalt. The turquoise blue color (objects 4, 6, 9) is caused by copper in the presence of iron. These same components (copper, iron) in the presence of lead (probably as lead anti-monate) produce a green color (object 2). Lead antimonate alone causes a yellow-orange color (object 3). Cowell and Werner (I) have found also that cobalt at the 0.2% level can impart a deep blue color, that antimony at the 2% level (as calcium antimonate) can produce an opaque white glass, and that copper in a certain form see below) at the 4% level can give a deep red color. These results are in general agreement with those found by other workers (5). 

Adulterated Pearl, made of very white glass. 

Figure 3 Photodegradation of different colchicine preparations during seven days-storage in diffuse daylight. (A) tincture of colchicum, white glass bottles, (o) tincture of colchicum, brown glass bottles, ( ) colchicum pressed juice, white glass bottles, (a) colchicum pressed juice, brown glass bottles. Source. From Ref. 9.

Figure 14 Photodegradation of chloramphenicol eye drops FNA depending on the container. (A) White glass ampoule, (B) LD-polyethylene container, (C) brown glass container, (D) LD-polyethylene container, white, opaque, (E) LD-polyethylene container in the carton. ( ) 6 weeks diffuse daylight, ( ) 6 weeks sunlight. Source From Ref. 6.

Figure 4. Sample No. 14122 (Roman) high alkali, coarse texture, continuous, hardness >3 Mohs, dark blue. Thefollotcing phases can be identified Egyptian Blue (white), glass (light gray), and quartz (dark gray).

By the seventeenth century perfumes had begun to be stored in lightly blown glass bottles, and the eighteenth century saw the appearance of pear-shaped bottles in opaque white glass, decorated similarly to porcelain ware. Weight was reduced, and decorative appeal achieved by colour, cutting and applique decoration, which made perfume bottles truly treasured possessions, and worth much to today s collectors. 

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