Black Amethyst Glass

By Dr. Beth J. Sanborn and Dawn Johnson

Black amethyst glass, a striking and mysterious style of glassware, has fascinated collectors and enthusiasts for centuries. Known for its deep, rich purple hue, which shifts to a black or dark shade when viewed in certain lighting, black amethyst glass has a unique history and many intriguing properties. This glass was first introduced in early 19th century Europe, and it quickly became a sought-after material due to its unusual appearance and the mystique surrounding it.

The origins of black amethyst glass can be traced to the discovery of a particular type of glass formula that incorporated manganese, a chemical element known for its ability to alter the color of glass. In its natural state, manganese produces a pale purple or amethyst color when used in glassmaking. However, when exposed to ultraviolet light or sunlight, this color can deepen, and the glass can appear nearly black, especially when viewed from certain angles. This effect is what gives black amethyst glass its signature look and allure.

The first known examples of black amethyst glass appeared in Europe during the early to mid-1800s, specifically in England and France. Glassmakers were experimenting with different chemicals and techniques to produce colored glass, and manganese’s light-reactive properties were recognized and utilized. Initially, the glass was used to create decorative items such as vases, perfume bottles, and jewelry. These items were prized for their unique color, which could range from a deep, velvety purple to a nearly opaque black.

During the Victorian era, black amethyst glass became particularly popular in the United States and Europe. The glass was often associated with mourning jewelry and accessories, as its dark hue symbolized death and loss.

In fact, black amethyst glass was sometimes referred to as “mourning glass,” and it was crafted into pieces like brooches, lockets, and rings, worn to commemorate the death of loved ones. These items were often inscribed with the names of the deceased and were a common part of the mourning rituals of the time.

While black amethyst glass was once a symbol of mourning, its use began to expand beyond this context by the late 19th century. By the turn of the 20th century, black amethyst glass was used in a variety of other items, including decorative pieces, serving ware, tableware, and bottles. The glass was prized for its ability to shimmer and change in different lighting conditions, adding an element of mystery and elegance to any collection.

In the 20th century, the use of manganese in glassmaking was phased out due to health concerns, as exposure to high levels of manganese can be toxic.* However, the legacy of black amethyst glass remains strong, with antique pieces continuing to be valued by collectors today.

Above, left to right: Early 19th-century blown amethyst glass cream jug (Los Angeles County Museum of Art). 19th-century pressed glass vase (Metropolitan Museum of Art). 19th-century bar glass (Los Angeles County Museum of Art).

Vintage black amethyst glassware can still be found at estate sales, auctions, and antique shops, and its historical significance has made it a treasured artifact for glass enthusiasts and beachcombers alike.

For collectors, black amethyst glass is a fascinating example of how the world of glassmaking can blend science, art, and history into something truly unique. Its mystique and dark beauty continue to captivate those who seek out the rare and extraordinary in their beachcombing adventures, making it an enduring treasure of the past.

*Note: Manganese is not absorbed through the skin, so it is safe to touch black amethyst glassware and sea glass. Avoid inhaling the dust from broken manganese glass or drinking from cracked or damaged manganese glassware.

All photos courtesy of Dr. Beth J. Sanborn and Dawn Johnson except as marked.

This article appeared in Beachcombing Magazine Volume 48 May/June 2025.