Characteristics: One letter per sound. Consonant mutations and broad/narrow consonant distinction marked by diacritics. Inflections change the appearance of a word minimally. Words are written with less letters than in standard Irish spelling.
The name Shelta is stolen from the name of the language spoken among Irish Tinkers (nomadic people), to suggest its nature as something akin to but not exactly Irish-y. Sorry, tinker people.
I. Consonant mutations
Table 1. Basic consonant rewriting rules
II. Broadness
A broad consonant is adjacent to one, or flanked between two broad vowels: a, o or u
A narrow consonant is adjacent to or flanked between two narrow vowels: i or e.
At times a flanking vowel is written not to be pronounced, but to indicate whether the consonant is pronounced in its broad (velarised) or narrow (palatalised) form. Since in Shelta narrow consonants are indicated with a dot below, these flanking vowels are no longer necessary and are not written.
Figure 1. Eliminating silent flanking vowels
To determine whether a vowel is pronounced, it would be necessary to use an audio guide or to have a native speaker read out a passage (which is why all my experiment passages are song lyrics).
The vowel "ao", which is pronounced something like a vague "eh", is rewritten as "y" in Shelta. It is a broad vowel.
Figure 1a. The vowel ao
III. The letter F
The letter F in Irish is only occasionally pronounced. It is usually absorbed into a preceding consonant in the middle of a word. When this happens, the preceding consonant is written with a circumflex and the f is dropped. An exception is with the cluster "bhF", which is an eclipsed F (see Table 1).
Figure 2. Dropping the silent f
IV. Diphthongs
There are places where a lenited consonant (bh, dh, gh, or mh) serve as an approximant or only to lengthen a vowel. Consequently, they lose their consonant status in Shelta spelling and is absorbed into the vowel as a diacritic indicating the identity of the absorbed consonant:
Figure 3. Contracting diphthongs
a. The Lord's Prayer in Shelta Irish
