My close-up vision has been deteriorating of late (sigh), which is a real hassle if you make glass beads. A beadmaker should wear special safety glasses, made from a material called didymium. Didymium glasses have a dual function: to protect the eyes from flying bits of hot glass, and to reduce the sodium flare from the melting glass. Sodium flare is a bright yellow flame which obscures the details of the bead; the special mauve-coloured didymium glasses cancel out the yellow flare so that you can see what you’re doing.
Anyway, didymium glasses are not cheap, even the ugly pair that I have was not cheap. Prescription didymium glasses are even more expensive. So for a while I resorted to wearing reading glasses under my safety glasses. My not-suitable-for-glasses nose was slowly dying under the weight. And every time a rod of glass exploded I would jump, and then my glasses would fall off their glasses. All in all, very irritating.
I finally came across this wonderful invention by Neoptx: stick-on bifocal lenses. Made from a special plastic which is pliable when wet but as hard and as clear as glass when dry. The lenses come in different strengths, and are removeable and reusable. Using them you can convert a pair of safety glasses, or a favourite pair of sunglasses, or a set of prescription glasses into a set of bifocals. I found a place here in the Amsterdam that could order them in, but the quoted price was a somewhat mind-boggling €35 for one pair of lenses.
In the meantime, via Lampworketc, a glass forum, I was led to this great little American company, StickonBifocals, which sells Neoptx lenses for a fraction of the price. International customers may order up to 2 pairs, so I ordered two different strengths. They arrived within 5 days, and cost $US 34, including shipping. In these rather weird financial times, where banks seem to be crashing about our ears, that works out to €25 for *two* pairs of lenses.
The lenses work as advertised. I now have pure 20/20 vision through my expensive, ugly didymium glasses. And, even better, there is no added weight. My nose is grateful.