What is sea glass?

Since I mainly use sea glass in my silver jewelry, the question arises: What is sea glass anyway?

Sea glass is ordinary glass, such as from bottles, vases, lamps, or windows, that found its way into the sea long ago. There, the shards were then shaped by waves, salt, sand, and stones for decades. Eventually, these original pieces of glass can be found, polished to a rounded shape, on beaches, where they wash up again. Sea glass is therefore essentially "trash" because it doesn't belong in the ocean, but it carries a long history and looks like gemstones that came from the sea. There are even pieces of sea glass that are centuries old. Furthermore, there are great differences in the rarity of certain colors. White and green sea glass, for example, are the most common, while blue is rarer. Red, yellow, or pink sea glass, as well as multicolored ones, are extremely rare. Another special type of glass is bonfire glass, which is molten glass and sometimes looks lumpy like chewing gum and can even contain ash inclusions. Safety glass is also a special find and can be identified by its wires within the glass. You also need extreme luck to find uranium glass, which dates back to the 1800s and glows under UV light due to the uranium oxides in the glass. Patterned sea glass is also rarer and equally beautiful.