Angerthas was called like that because they extended the Certhas of Daeron and added several more cirth. The adding of 2 whole new rows (CH-row and QU-row) was attributed to them.
The addition of these caused the following: a new certh for h to replace the previous certh # which became ch. This certh was preferred for ch because its shape seemed to be between the shapes of the T and K cirth (8 T + e K > # CH), to represent how the ch sound also (phonologically) exist between t and c. There was also a new certh for nd, which as Tolkien notes, its form wasn’t much related to the dental cirth.
Some of the new letters were used for sounds of Quenya (and other tongues) not found in Sindarin. In that stage, the Angerthas reached its fullest extent, but for most forms of writing other than carving, the Tengwar were used.
- This certh was used for h, but was chosen for ch, as it occurred phonologically between sounds t and c, and its shape looked intermediate between the Cirth 8 and e. Not to be confused with Sindarin ch!
- Since it represents the labialised sound kw (also spelled qu), its shape was maybe a mixture of the Cirth 8 and 1.
- Tolkien shows two distinct signs for s as indifferent. Their exact use can’t be guessed and isn’t obvious like the relation of the tengwar Silmë and Silmë Nuquerna.
- Tolkien gives the value z to that letter (in alien systems?), but notes it was ss when used in Quenya and Sindarin.
- Maybe near that time, this new certh was made for the value of h, similar in shape to the former # (and to the tengwa Hyarmen 9).
By the Second Age the Tengwar were the dominant writing script, but the Gwaith-i-Mírdain used the runes in formal documents, as a "matter of lore".[note 2] The Noldor made use of the cirth and made a name for them in Quenya, Certar.
- Cf. Robert Foster, The Complete Guide to Middle-earth, entry "Angerthas Daeron". Jim Allan in An Introduction to Elvish also identifies "Angerthas Daeron" with the writing of Eregion, but later gives the name "Angerthas Eregion" to their "full expansion". In the chronological table, he uses only the name "Angerthas Eregion" while the previous versions are dubbed "Early Daeron" and "Late Daeron".
- The text explains this by saying that Celebrimbor was a descendant of Daeron; however this was written before deciding that he was the son of Curufin.