Contributed by www.Marks4Antiques.com – a membership-based service specializing in providing identification & appraisal advice on antiques & collectibles.
There is as much difference in the color of glass, meaning only transparent colorless glass or crystal, as there is in the color of diamonds. The beauty and value of antique Glass or Crystal, just like in the case of Precious Stones, are measured very largely by its perfection.
Fine antique glass should be of a purity that practically renders it invisible without any trace of yellow or green cast or opacity. Sometimes it will have a slightly bluish white color. Antique Glassware that otherwise seems clear with respect to its color when seen by itself will often appear at a decided disadvantage when placed beside a really fine piece.
Modern detergents and the use of a good bottle brush will generally suffice for removing the usual discoloration caused by the contents of decanters, cruets, perfume bottles, etc. Where cloudiness or stain persists, many remedies have been suggested and tried with varying degrees of success. Among them:
- The use of Polident (used for cleaning false teeth)
- Liquid Plumber (used for clearing clogged drains – highly caustic and requires careful handling)
- Adding uncooked rice to vinegar and shaking vigorously
- Using a tea bag with vinegar and letting it soak for 24 hours
- Allowing chopped potato peel with a small amount of water to stand in a bottle overnight
Oiliness may be removed with alcohol left in for about 15 minutes. In each instance, the item should be thoroughly rinsed and dried afterwards. Strips of cloth may be inserted into bottles to dry them and then removed with a heavy wire or hook.
To obtain the best results, polishing was done in three stages. First, it was done with wooden wheels fed with pumice, stone and water; then brush or wool wheels with the same preparation, and lastly cork or felt wheels with finely compounded putty powder. About the turn of the century, the acid bath, quicker and less expensive came into use for polishing. It was hand-burnishing, however, that gave the superb brilliance down to the smallest detail.
Working the lather into the cuttings with a soft brush, or toothbrush will enhance the brilliance of the deeper and more intricate incisions. The glass should then be dried without draining on a soft towel. When perfectly dry, the cut surfaces should be gone over again with a clean dry brush. A soft, lint free cloth should then be used to give it a high polish.
Antique Glass which continues to cloud up after cleaning and rinsing is known as “sick glass.” It is caused by the formation and separation of crystals due to imperfect fusion of the metal or too high an alkaline content in the making. It can be professionally polished off and then “glass wax” applied if the area can be reached. Frequent applications of the wax will be helpful in delaying further deterioration. Unfortunately, this remedy is usually not practical where it is needed most – in the cleansing of bottle type containers.
The use of ammonia or strongly alkaline soaps on antique Glass or Crystal should be avoided. Extreme and sudden changes of temperature may also be harmful. Before using ice-cream platters, punch bowls, sherbet glasses or other pieces designed for frozen foods or chilled beverages, the glass should be allowed to stand for a few minutes in a cold place or held under a jet of cold water.
Cut glass with sterling silver mountings was once very popular. To this very day, many people consider the use of sterling articles with cut glass as the basis for the most elegant table settings. However, each section must be carefully cleaned using a different ‘set of rules’. In general, in cases of antiques that are made of a mix of different materials, please be careful so as not to have certain chemicals or cleaning agents suitable for one material come in contact with other parts.
For information and useful advice on cleaning Metal items, including Antique Sterling Silver or Antique Silverplate, please see another article on www.Info4Antiques.org under the “SILVER & JEWELRY” section.
You can also read the article, CARE, CLEANING and CONSERVATION METHODS for ANTIQUE METAL WARE: Useful tips in restoring Antique Lamps, Clocks, Ormolu, Spelter, Bronze etc, right here on the Antiques.com blog! We’ll be posting this article next so be sure to come back for these useful tips!