Sea Glass Glossary A-Z

Sea glass originating from art glass or decorative household items, typically rare and cherished.

Some sea glass embedded in the sand can become coated and algaefied over time. This results in a false pale green colouration. Once cleaned the true colour of the glass becomes apparent.

The warm brown colour of certain types of sea glass. Thinner brown sea glass typically features the lighter amber colouration.

Distinctive pale blue-white variety sea glass.

Re-finishing shaped or uncooked sea glass in a geological tumbler to create a smoother and refined piece of sea glass for jewellery.

Beach glass describes sea glass found on the beach. This term also describes glass found on the shore of a fresh water lake. However, glass found near freshwater sources cannot be described as sea glass.

Glass shaped by blowing air through a hollow rod into molten glass, usually seamless with a pontil scar.

Massive, round sea glass pieces often originating from slag or cullet glass, sometimes weighing over 8 pounds.

Sea glass melted in a fire before being smoothed by the sea. Typically features a bumpy texture sometimes with carbon matter.

The most common sea glass type, originating from old bottles and jars, dating back to the first hollow glass container made in 1500 BC. Bottles discarded on beaches and lost from boats break and weather to create most of the sea glass found on the shore.

One of the most common sea glass colours. Shades vary from olive green to bright bottle green.

Small, almost perfectly round pieces of sea glass seldom found, sometimes also called gemballs.

Black sea glass is extremely rare. In fact, most sea glass with a black appearance reveals some colouration, typically brown or green, when held up to the light.

Colorful rods wrapped around each other, creating unique patterns often seen in sea glass.

Shape of the natural pitting found on genuine sea glass. Close inspection reveals many crescent-shaped indents typical of true sea glass.

Crazed lines appearing within the glass due to sudden changes in temperature.

Raised patterns or text on glass, providing clues to age and origin, desirable in sea glass pieces.

Sea glass exclusively from Seaham and Tyne and Wear regions in England, byproducts of historic glassmaking.

Modern glass, treated to mimic the aging process of natural sea glass formation, artificially enhanced through abrading the surface of modern glass. Genuine sea glass features pitting and textures seldom seen on fake examples.

Distinguishing parts of sea glass, including bubbles, embossing, shape, and thickness, indicating age and origin.

Discarded punty tips from the glassmaking industry.

Flat rolled glass with two or more colours, used for windows, often found in sea glass form. Some bottles such as Mermaid gin use glass laminated in this way with colours to create the impression of coloured glass bottles.

A form of sea glass art where pieces are laid out on a flat canvas to create a design.

Non-production glass pieces made by glassmakers, often found in sea glass form.

White, frosty appearance on sea glass, indicating long-term exposure to salt water.

Round spherical pieces of sea glass, marble-shaped derived from a variety of origins.

Natural sea glass formed over time without any artificial treatments.

A term used for the clear white examples of sea glass. Glacier white reveals a semi transparency different to white sea glass with a heavy frosted texture.

The halo effect accounts for one of the reasons some sea glass stands out on the beach. Lighter colour pieces of sea glass often leak light through the edges resulting in a ring of light, or halo around the glass.

Glass found on the beach likely to cause harm to wildlife, dogs or walkers. Some can be shaped and utilised, but generally such items are removed for safety reasons. Typical examples include broken bottle glass from visitors leaving waste on the beach.

Process in which hydrogen ions replace sodium ions in glass, contributing to the aging and frosted appearance of sea glass.

Sea glass with a pleasing shape, even frosting and lacking chips and breaks. Suitable for making into jewellery without any shaping.

Steep rises in the base of a bottle, enhancing strength and stability, often found in sea glass form.

Describes long slender examples of sea glass with a classic lozenge shape.

Distinctive green colour of yellow-green sea glass.

Round sea glass pieces originating from children's toys, ballast, or Codd bottle closures.

A quaint alternative name for sea glass, typically describing the white, semi-transparent colour of sea glass. Legend tells of Mermaids shedding tears at the death of sailors drowned at sea.

Italian for "thousand flowers," a technique involving multicoloured glass canes used in sea glass.

Neck, as in bottle-neck. Tubular section of a bottle neck, sometimes found complete or partial.

Oiling is a technique to reveal the colour of heavily frosted sea glass when the colour is disguised by the rough frosted texture. Rubbing with a small amount of mineral oil enhances the colour of the piece.

Sea glass with distinctive patterns or embossing, indicating former decorative or product usage.

This is the natural textured surface with frosting and pitting. Patina builds over time—the desirable natural finish of genuine sea glass.

Small "C"-shaped marks under a microscope, indicating genuine sea glass formed naturally.

Glass tips from punty rods of the glassmaking industries, showing internal colour stretching.

Irregular pits on sea glass from years of tumbling, indicating age and natural formation.

Metal rod used in glassmaking, leaving visible scars on finished products, also seen in sea glass.

Factors like colour, size, condition, and origin determine the rarity and value of sea glass. For example, red sea glass represents one of the rarest and more expensive colours.

Sea glass from threaded bottle tops, common in the 20th century with various ridge designs.

Describes one of the rarest colours of genuine sea glass. Often priced higher compared to greens and browns.

Sea glass pieces from bottle bottoms, often thicker and sometimes embossed with a radial pattern.

Sea foam describes the classic pale green colouration of sea glass. The colour is due to the presence of iron, often from sand used in the glass making process.

A frowned-upon practice of depositing new glass pieces onto beaches in order to add to the amount of sea glass available in the future.

Piece of sea glass, more correctly termed a "remnant" because "shard" usually refers to broken pieces of pottery (potsherds).

Opaque pressed glass with coloured streaks, often found in sea glass form from old glass dumps.

Term for multiple tiny drilled sea-glass pieces stacked together to create an item of sea-glass jewellery. View example of seaglass stacking necklaces.

Glass bottle stoppers, often found in sea-foam green, used before commercial closures.

Glass that turns purple from long-term sun exposure due to manganese content.

Sea glass found and then discarded intentionally. Throwbacks are often poorly shaped, or not aged enough.

Glass made with swirled colours from leftover batches, a practice to avoid wasting materials.

Sea glass in its natural state, not artificially shaped or frosted.

Uncooked describes new glass found on the beach without the frosted finish of aged sea glass.

Non-production glass pieces made by glassmakers, often found in sea glass form.

The highest point of shingle on the beach where the tide reaches. Often a good place to start looking for sea glass, marked by a deposition of sea weed.