Uranium / Vaseline Glass Inkwell

This is a beautiful colored inkwell made from uranium, or “Vaseline,” glass.

• Color and Appearance: The inkwell has a vibrant, translucent yellow-green color. The glass is faceted with multiple cut surfaces on both the main body and the lid, which allows light to catch and reflect in a brilliant manner. The color is characteristic of glass made with uranium oxide.
• Form and Construction: The inkwell has an octagonal or multi-faceted shape, giving it a geometric, jewel-like quality. The lid is also faceted and fits over the opening of the inkwell. It is attached by a hinged brass collar.

The Process for Achieving its Color

The unique yellow-green color of this glass is achieved by a specific and now somewhat rare process involving the inclusion of a particular chemical compound:

• Uranium Oxide: The distinctive color is created by adding a small amount of uranium oxide (U3​O8​) to the molten glass mixture. The concentration of uranium is typically very low, usually less than 2% by weight.
• Fluorescence (The “Vaseline” Effect): The most defining characteristic of this type of glass is its strong fluorescence under ultraviolet (UV) light, which is where it gets its popular name “Vaseline glass.” When a UV light source is shone on it, the glass emits a brilliant, glowing green light. This is a direct result of the uranium content.
• Historical Context: The use of uranium in glass was a common practice from the mid-19th century until about the mid-20th century. Production was largely halted after World War II when governments began to restrict the use of uranium for security and nuclear-related reasons.