I am just putting the finishing touches to my entry for the Esty Beadweavers Monthly Beadweaving Challenge. The theme this month is Simon and Garfunkel. My entry - ‘Thyme is golden’ (see photo) inspired by Scarborough Fair - is in soft green and gold tones and it includes several crystals lovely sparkling sage tones – the last of those beads in my stash. I’ve been watching the play of light on the crystals and I started to wonder – what creates those wonderful sparkles and why is it that some crystals sparkle more than others. What is in a sparkle?
It may surprise you to know that much of the sparkle is produced by lead oxide. When lead oxide is added to molten glass if forms lead crystal. The addition of lead creates a high index of refraction or in the colloquial a high index of sparkle. It also makes the glass clearer, heavier and much less likely to crack when carved or etched. Regulations in Europe specify that to be named “lead crystal” the glass must contain 30% or more lead. Anything below that amount can just be advertised as “crystal.”
Lead oxide is toxic if when introduced into the bloodstream (for example by swallowing it). It can cause memory loss, nausea, depression, fatigue, joint pain, abdominal cramping and vomiting. Most manufacturers, including the famous Swarovksi glass bead makers, argue that simply wearing or touch crystal lead jewelry does not expose you to enough lead to be toxic because the lead is not easily released from the beads.
Lead can be leached from glass and into our bloodstream when it is exposed to highly acidic environments over an extended period of time (for instance, when a lead decanter is used to store alcohol or orange juice for some months). Clearly, we don’t drink from crystal beads but there are a couple of ways in which lead can be leached into our blood stream from products with lead in them. First, if components containing lead are sucked or swallowed, saliva and/or stomach acids could leach the lead out into the body. Second, if we in some way heat jewellery items with lead in them, toxic fumes can be released which we then inhale. As our skin contains acid I found some sites online recommending that to be safe after you have worked with crystals you wash your hands before touch or preparing any food and to totally avoid lead crystal in jewelry for young children (who may accidently ingest the beads).
Given that I am no authority on these issues and that it is difficult to find authoritative advice online I’d welcome your thoughts or knowledge on these issues. If you know of a good source of authoritative information I’d love to hear about it and share it. I think as in most things, exercising caution is probably a wise route.
Useful sites to consider the issues further:
- RingsNThings jewelry supplies: http://www.rings-things.com/jewelry-safety.html
- Californian Department of Toxic Substances Control: http://www.dtsc.ca.gov/LeadInJewelry.
- Waren Wilson: A site that lists recalls of products that contain dangerous levels of lead including items of jewelry: http://www.warren-wilson.edu/~lpp/news.html