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Curing Sick Glass
Reyne and glassware
Reyne Haines says sick glass affects novice and expert collectors alike.

You're probably familiar with sick children and sick minds and perhaps sick buildings, but there's another kind of sick that concerns Reyne Haines, of Just Glass Auctions in Cincinnati, Ohio. While working in the vintage glass business, Reyne has been unfortunate enough to see a doctor's share of what's known as "sick glass." This malady coats sparkling or transparent glass with an unwanted fog, and as Reyne points out, it's an illness that afflicts the glass of both novice and experienced glass collectors.

Unlike the patina that develops on an old piece of furniture, this foggy frost is not a welcome addition to any glass. "Besides cracks and chips, it's the number one turn-off in glass," Reyne asserts. "It's considered damage." Even if it's not chipped or cracked, most serious collectors won't buy a piece of sick glass, Reyne notes. If they do, they'll only pay a fraction of the price that they would put out for the same unblemished piece.

"It's not something that affects just old glass," Reyne adds. "You might see it in a vase you received from friends last year or in the drinking glass you just pulled from your dishwasher." In her 10 years in the glass trade, Reyne has discovered a good number of remedies to cure sick glass, no matter what type of glass it is. She's shared what she's learned with ANTIQUES ROADSHOW. who have them from their childhood, bring them in to find out their value."

The "Sick Glass" Culprit: Calcium

Tumbler with candle-wick pattern
This Candlewick-pattern tumbler suffers from "sick glass" syndrome.

To understand how to clean sick glass, it helps to know what causes it. It's no accident that the malady most often afflicts glass that is filled with water, such as vases, bowls, or drinking glasses. That's because most water, especially the variety that runs from your tap, contains dissolved mineral deposits, including calcium. The calcium, which exists in high concentrations in water that is considered "hard," is near invisible until the water evaporates, leaving calcium deposits behind. That's why the term "cloudy glass" is also used to describe calcium-coated glass, Reyne says.

What to Start With
In cases where the calcium build-up is light, Reyne recommends an old-fashioned mix of water and vinegar. Glass owners also put on some petroleum jelly overnight on cloudy glass, or rub the glass with ammonia and water, the components used in glass cleaners such as Windex. However, Reyne points out that both of these latter prescriptions are only temporary fixes.

"They only mask or hide the damage," says Reyne, who makes an analogy with putting lotion on dry skin. "When the lotion sinks in, the problem comes back. It's not removing the problem, it's hiding it."

All too often, Reyne says that people desperate to clean their clouded glass will soak it in straight ammonia or hydrochloric acid. These strong chemicals will eat through the calcium, but they don't stop there. They also eat into your glass, leaving rough spots that look like "craters on the moon," Reyne says. There are no easy remedies for that damage.

Calcium fogged vase
This vase—fogged by calcium deposits—was made around 1940 by Anchor Hocking.

Reyne has learned about some less common remedies through an email glass discussion group that she hosts on TIAS.com (The Internet Antiques Shop), an online antiques mall. "I teach them and they teach me," says Reyne of the online participants, adding that she has had success with each of the following suggestions. Reyne notes that she and other glass lovers search hard for the perfect cleaning solution with the assumption that "there has to be something that can fix a homeless piece of glass."

Usually reserved for teeth, toothpaste or a denture whitener also takes calcium off glass. These teeth cleaners also clean the tar deposits from cigarette smoke off old glass. Reyne does it like this: She puts a dab on her index finger rather than a toothbrush and then gives the glass a gentle rub.

Bathroom cleaners also seem to be effective calcium cleaners. Tub and tile cleaners have worked on some glass; Reyne also recommends cleaners designed to take calcium deposits off of glass shower doors. Asserts Reyne: "These are some of the best glass cleaners."

Whatever cleansing agent you use, Reyne says you shouldn't let the chemicals sit on the glass for long. Wash it off immediately with some mild soap and rinse it with luke-warm water. "If the water is too cold or too hot, the glass will crack or shatter," warns Reyne, noting that people often forget that "glass is very fragile."

Preventative Measures

Clear glass
Glass is more valuable when not clouded.

Perhaps the best way to keep your glass free of calcium deposits is to never let it build up in the first place. "Don't let water stand too long in glass," Reyne says. Keeping water out of glass prevents it from evaporating and leaving calcium behind. After you empty the glass, wash it out with mild soap and water. Don't let it air dry, Reyne suggests. Instead, dry it off good with a dishrag.

And if deposits do build up, don't despair. "Lots of glass was not made to sit pretty on a shelf," Reyne explains. "They were working pieces, so deposits from water should be expected."


To learn more about collecting glass, Reyne recommends the following books:

Forence's Glassware Pattern Identification Guide
Gene Florence, Collector Books, 1998.
This book displays machine-made collectible glass from the 1920s-1960s.

The Collector's Encyclopedia of American Art Glass
John Shuman III, Collector Books, 1994.
This book features handmade glass from the Victorian era to the 1930s.



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