Bronze Age
Bronze Age cultures differed in their development of the first writing. According to archaeological evidence, cultures in Mesopotamia (cuneiform script) and Egypt (hieroglyphs) developed the earliest viable writing systems.
The overall period is characterized by widespread use of bronze, though the place and time of the introduction and development of bronze technology were not universally synchronous. Human-made tin bronze technology requires set production techniques. Tin must be mined (mainly as the tin ore cassiterite) and smelted separately, then added to molten copper to make bronze alloy. The Bronze Age was a time of extensive use of metals and of developing trade networks (See "Tin sources and trade in ancient times"). A 2013 report suggests that the earliest tin-alloy bronze dates to the mid-5th millennium BC in a Vinča culture site in Pločnik (Serbia), although this culture is not conventionally considered part of the Bronze Age. The dating of the foil has been disputed.
Undeciphered writing systems
Certain forms of proto-writing remain undeciphered and, because of a lack of evidence and linguistic descendants, it is quite likely that they will never be deciphered.The following is a list of undeciphered scripts from the Bronze Age (3300 to 1200 BC).Many Mesoamerican writing systems have been discovered by archaeologists. Many of them remain undeciphered due to a lack of knowledge of the original language. These writing systems were used between 1000 BC and 1500 AD.One very similar concept is that of false writing systems, which appear to be writing but are not. False writing cannot be deciphered because it has no semantic meaning. These particularly include asemic writing created for artistic purposes. One prominent example is the Codex Seraphinianus.