seal fragment HM 992, showing a single symbol, identical to Phaistos Disk glyph 21.
The relation of the last three items with the script of the main corpus is uncertain.
Some Cretan Hieroglyphic (as well as Linear A) inscriptions were also found on the island of Samothrace in the northeastern Aegean.
It has been suggested that there was an evolution of the hieroglyphs into the linear scripts. Also, some relations to Anatolian hieroglyphs have been suggested:
The overlaps between the Cretan script and other scripts, such as the hieroglyphic scripts of Cyprus and the Hittite lands of Anatolia, may suggest ... that they all evolved from a common ancestor, a now-lost script perhaps originating in Syria.
Symbol inventories have been compiled by Evans (1909), Meijer (1982), and Olivier/Godart (1996).
The glyph inventory in CHIC includes 96 syllabograms representing sounds, ten of which double as logograms, representing words or portions of words.
There are also 23 logograms representing four levels of numerals (units, tens, hundreds, thousands), numerical fractions, and two types of punctuation.
Many symbols have apparent Linear A counterparts, so that it is tempting to insert Linear B sound values. Moreover, there are multiple parallels (words and phrases) from hieroglyphic inscriptions that occur also in Linear and/or Linear B in similar contexts (words for "total", toponyms, personal names etc.)
The sequence and the geographical spread of Cretan hieroglyphs, Linear A, and Linear B, the three overlapping, but distinct, writing systems on Bronze Age Crete and the Greek mainland can be summarized as follows:
^Metaxia Tsipopoulou & Erik Hallager, The Hieroglyphic Archive at Petras, Siteia (with contributions by Cesare D’Annibale & Dimitra Mylona). Download PDF file 60 MB Monographs of the Danish Institute at Athens 9, Athens, 2010 ISBN978-87-7934-293-4