We at Tecnolux coat blacklight tubing. The glass is made by Philips and has a very dark filter. It is lead glass. The down side is that it only comes in 15mm and 25mm. Also they are hot cathode blanks so they have a very thin wall. 1mm. It is almost possible to work with and very expensive. As far as I know it does not come in 10mm. We have the 15mm in stock Just call for samples. David (800)333-6366