The general consensus among Domincians I have spoken to is that Almy (yes, I know they are Episcopalian) mades the best academic birettas, but it will take about a month to get one made. If you call them on the phone, you can specify whether you want folding or rigid, what kind of cloth (poly or wool blend), what color, 3 or 4 fins, what color piping, whether a pom or not. This is important if you have special requirements. E.g. the *traditional* Angelicum biretta is entirely white (incl. piping and pom).
Gammerelli in Rome can do a quick turn around if you are in a real rush. They have all sorts of academic birettas in stock (be sure to know your European hat size). But be warned: their pom is very odd and comes tied up. Do NOT untie it for it will flop over and look even worse. If they don't have what you need in stock, I say call Almy.
Does the individual need an academic ring too? I recently went through a lot of trouble to find out what they should be like--modern canon law no longer specifies. The older canonists (Dictionnaire de droit canonique) say only that it should be simple and have at most one stone. And that the traditional stone was an amethyst (like that traditional for a bishop. If you need it fast, "gemhut" on the web can do a "gents ring" which is noble and simple in gold with a nice emerald cut amethyst for under $700.
Those with degrees from a non-pontifical university cannot wear an academic biretta, they wear the cap or morterboard of their degree granting institution. The biretta is the sign of an ecclesiastical (pontifical) degree.
The traditional colors, at least in my experience are theology=red, canon law=green, philosophy=white. These would be the color of the piping and pom, if that were the practice at the institution involved. But remember that some schools use different color arrangements for their birettas. For example, as above, the traditional theology biretta of the Angelicum is totally white.
It is pretty much universal that the license is three finned and the doctorate four.
But the "Magister Sacrae Theologiae" an honorary degree given by the Dominican Order (which is actually beyond the doctorate), has four fins, even if it is called "master." This is because "magister" and "doctor" meant the same thing in the middle ages.
Traditionally religious did not wear academic robes over their habits, since the habit is already a robe. The hood of the degree and whatever was the suitable headgear were worn with the habit and that was it. I am told that secular clergy similarly wore the hood and cap with cassock and suplice, but I have not been able to confirm that.
Watts & Co
House of Hansen
Some articles on Gammarelli:
Tailor to the Popes Working Overtime (washingtonpost.com)
Style secrets of the pope's tailor : Religion : Naples Daily News
The Cloak & Soutane Trade - TIME
The Ritual Behind the Ritual
Annibale Gammarelli in front of his tiny tailor shop that served ...
The discreet business of dressing a pontiff - World - www.theage ...
(via archive) Ditta Annibale Gammarelli Abiti Ecclesiastici E ...
Ditta Annibale Gammarelli Abiti Ecclesiastici E Paramenti
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