#lead crystal

Andra Ursuţa  Impersonal Growth, 2020

Lead crystal

Left: A 100+ year old medicine bottle that my parents dug up in their backyard when I was a kid. Their house is built where the old municipal dump was in the late 1800s, so there were lots of bottles like it buried in the dirt. Right: An ordinary wine glass from the 1990s. Both of these things have been sat on a shelf gathering dust for over a decade.

...Until recently, when I got my hands on a UV flashlight.

[Video description: The bottle and wine glass described above sit next to each other on a table, with the bottle on the left and glass on the right. They are lit from above by a normal incandescent bulb, though the bulb is out of shot. There is a plastic squeaking sound, and the light dims and turns off, leaving the screen dark. There is a click, and a UV flashlight turns on off screen, to the left. Under its light, the bottle glows yellow-green, and the wine glass glows blue. The light holds for a few seconds, then turns off with another click, leaving the screen dark until the video cuts out.]

They glow!!! (These two aren't the only ones either, just the ones with the brightest color.)

There are a lot of different things that can be mixed into glass to make it fluoresce under UV (including, perhaps most famously, uranium). After doing some research, I think I've pinned down these two.

The bottle has manganese, which was (ironically) used to remove the green tint from glass and make it colorless.

The wine glass has lead, which increases the reflectivity of glass to make it more sparkly (and can also leach off into your drink and give you lead poisoning. Whoops!)

As I'm sure you can tell I've been nerding out over this big time. I love when science is pretty :)

New bedside water "bottle"

Glasses: Lead Crystal

Known as lead crystal, crystal, or lead glass, this material is similar to other glasses, in that the main component is silica, but also contains lead oxide. There is no set definition for lead crystal glass but some people consider glass with over 24% lead oxide to be lead crystal and under 24% to be simply crystal glass. Lead replaces the calcium content of a typical glass.

The addition of lead oxide increases the clarity of the finished glass by increasing both the refractive index and the density. Lead also increases the so-called 'working period' of the glass, making it easier to shape. It is not a crystal, as it is still an amorphous solid. Lead crystal glass is heavier than other glasses and makes a sharp, clear sound when struck.

In modern times, due to increasing awareness of lead's negative health effects, the popularity of lead crystal glass has greatly decreased. Nevertheless it still has several applications. While the most common usage is in dinnerware, drinking glasses, and ornamental glassware, lead crystal glass is also used in optical applications, glass sealants, and in radiation shielding (specifically from gamma and x rays).

Currently, most health officials recommend that lead glass is used sparingly and that beverages are not stored within lead glass containers for any significant lengths of time, and that children avoid lead crystal. Lead does leach into glassware, but after only a few hours it is still less than the quantity of lead in an ordinary diet - which is not to say that any consumption of lead is necessarily safe, only that occasional and infrequent use should be alright.

Sources/Further Reading: ( 1 ) ( 2 - images 1 and 2 ) ( 3 - image 4 ) ( 4 )

Lead Crystal