Per the cross family precedent (http://heraldry.sca.org/loar/2009/05/09-05cl.html):

From Wreath: Crosses and Substantial Difference

Given the widespread support for the proposal, we are implementing Batonvert's proposal on crosses that appeared on the Cover Letter for the August 2008 LoAR. Substantial difference under X.2 will henceforth be granted between crosses appearing below that do not belong to the same family. The families are:

Plain crosses couped, including Latinate and humetty.

Crosses flory, floretty, patonce, clechy, Calatrava, and Santiago.

Crosses crosslet and bottony.

Crosses moline, sarcelly, recercelly, anchory, fourchy, and miller.

Crosses formy/paty. (see the note, below)

Crosses doubled, patriarchal, and Lorraine.

The cross potent/billety.

The Tau cross.

The cross of Calvary.

The cross of Toulouse.

The cross gringoly.

The cross pomelly/bourdonny.

The Maltese cross.

We note that, in period, the term paty could refer to crosses in the flory family. The formy/paty family is not intended to overlap these two groups, we are using the SCA blazon term.

Standard period variants of a particular style of cross will not be considered separate; no difference is granted for fitching, changing between equal-armed and Latinate, etc.

Substantial difference between crosses is not limited to the above list. It is, instead, intended to provide a set of guidelines on the most frequently seen crosses in heraldry. All rulings of substantial difference which are not addressed by the above list remain in force, as do all rulings on significant difference.

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A new feature set has been defined: cross_family

The values are:

 calvary|cross_family
 crosslet|cross_family
 doubled|cross_family
 flory|cross_family
 formy|cross_family
 gringoly|cross_family
 maltese|cross_family
 moline|cross_family
 other cross|cross_family
 plain cross|cross_family
 pomelly|cross_family
 potent|cross_family
 tau|cross_family
 toulouse|cross_family

I've gone through and extracted every distinct phrase in blazons that map to each (and sometimes more than one) feature.

calvary

cross of Calvary potent cross of Calvary cross calvary patriarchal cross calvary orthodox botonny =crosslet= Celtic cross bottonny, mounted on three grieces cross botanny cross botonny cross bottonny cross bottonny fitchy cross bottony cross bottony fitchy cross bottony pierced cross bottony quarter-pierced cross crosslet cross crosslet Calvary cross crosslet fitchy cross crosslet fitchy quadrate cross crosslet fitchy square pierced cross crosslet fitchy square-pierced cross crosslet formy fitchy cross crosslet voided cross Latin bottony cross of Saint Julian cross of St. Julian cross patriarchal bottony cross-crosslet fitchy cross-crosslet quarter-pierced crosslet crusilly crusilly fitchy crusily crusily (sometimes fitchy) crusily bottony crusily crosslet fitchy crusily fitchy Latin cross bottonny latin cross bottony Latin cross bottony Latin cross crosslet Latin cross-crosslet Latin crosses botonny Latin doubled cross crosslet patriarchal cross bottony patriarchal cross calvary orthodox botonny patriarchal crosses crosslet Russian Orthodox cross botonny graded three passion cross botonny

doubled

cross couped of three crossbars missing the dexter base arm cross couped of three crossbars, missing the dexter base arm cross Lorraine cross Lorraine fitchy at all points cross of Lorraine cross patriarchal cross patriarchal bottony double cross doubled cross Eastern Orthodox cross Greek Orthodox cross Latin doubled crosses crosslet Lorraine cross patriarchal cross Patriarchal cross patriarchal cross botonny patriarchal cross bottony patriarchal cross crosslet patriarchal cross fitchy patriarchal cross fleury patriarchal cross flory rogacina doubly crossed and fourchy Russian cross Russian Orthodox cross Russian Orthodox cross botonny graded patriarchal cross calvary orthodox botonny

flory

cross clech{e'} cross clechy cross clechy fitchy cross clechy pommetty cross clechy voided cross crosslet fleury concave cross crosslet flory cross fleuretty cross fleury cross fleury azure irradiated cross fleury fitchy cross fleury fitchy cross fleury quadrate cross floretty cross flory cross flory fitchy cross flory tripartite cross formy floretty cross of Calatrava cross of four fleurs-de-lys conjoined at their bases cross of Santiago cross patonce cross patoncy cross pattonce cross sable a cross potent (later floretty) cross triparted and fretted fleury cross triparted and fretted fleury crosses formy patonce crusilly clechy crusilly fleury crusilly flory crusilly Latin Celtic flory crusilly Latin fleury crusilly patonce crusilly patoncy crusily flory crusily Latin flory equal-armed Celtic cross clechy equal-armed Celtic cross flory four demi-fleurs conjoined in cross Latin cross clechy Latin cross fleury Latin cross fleury fitchy Latin cross floretty Latin cross flory Latin cross formy floretty Latin cross patonce Maltese cross patonce Maltese cross patoncy patriarchal cross fleury patriarchal cross flory patriarchal cross flory azure

formy

Celtic cross formy Celtic cross patty cross crosslet formy fitchy cross formy cross formy convex cross formy fitched cross formy fitched at the foot cross formy fitchy cross formy fitchy at all points cross formy floretty cross formy nowy cross formy nowy quadrate cross formy patonce cross formy quadrate cross formy quarter-pierced cross formy swallowtail cross formy swallowtailed cross formy voided cross pat{e'}e quadrate cross patee quadrate cross patt{e'} cross patt{e'}e cross pattee cross patty cross patty elongated in pale cross patty fitchy cross patty sarcelled cross paty cross paty fitchy cross paty fitchy crusilly formy crusilly Latin formy crusily formy fitchy crusily patty equal armed Celtic cross formy equal-armed Celtic cross formy Latin cross formy Latin cross formy fitched at the foot Latin cross formy floretty Latin cross formy nowy Latin cross formy swallowtailed Latin cross patty passion cross, ends formee

gringoly

cross gringol{e'}

maltese

crusily Maltese long Maltese cross long Maltese cross nowy pierced maltese cross Maltese cross Maltese cross elongated to base Maltese cross fitchy Maltese cross nowy Maltese crosses patoncy Maltese Latin cross

moline

cross moline disjointed cross moline crusilly moline cross moline nowy cross moline fitchy Latin cross fourchy cross moline notched of all four cross fourchetty cross miller cross of four anchors conjoined at the ring long cross moline cross forch{e'}es cross moline disjoined cross moline quarter-pierced cross moline disjoint Latin cross moline cross fourchy cross moline nowy quadrate cross Moline cross moline voided Two millrinds in cross cross mill-rind

other_cross

ankh Bowen cross Bowen knot crosswise bowen knot in cross Canterbury cross celtic cross Celtic cross Celtic cross fitchy Coptic cross cross alis{e'}e cross alis{e'}e fitchy cross annulety arms formy and voided - really; looked at the picture cross argent griffee-de-loup, pierced cross avellane cross avellane dismembered cross barby cross barby fitchy cross bretessed couped cross couped of chain cross couped rayonnant cross couped voided ending in four two-towered castles cross crescenty cross ending in four pheons cross erminy cross fleury azure irradiated cross formed of six white-based opals proper cross glandular saltirewise cross gurgitee cross gurgity cross nowy quadrate couped cross of Canterbury cross of Cerda{n~}a cross of Cerdana cross of chains couped cross of Cleves cross of ermine spots cross of ermine tails cross of fire rayonny cross of five lozenges cross of five mascles cross of four arrowheads cross of four ermine spots cross of four ermine spots conjoined cross of four ermine tails cross of four fusils cross of four lozenges cross of four lozenges nowed at the center cross of four mascles cross of four mascles pometty cross of four passion nails cross of four pheons cross of four pheons conjoined at the points cross of four pheons points to center cross of four seaxes conjoined at the pommel cross of four swords conjoined at the points cross of lozenges cross of Saint Bridget cross of Saint Brigid cross of Samildanach cross of St. Brigid cross of swords tips to center cross patty sarcelled - looked at the picture I did... cross pointed cross pointed raguly cross pointed, voided and interlaced cross quadrate couped cross swallowtail cross swallowtailed cross swallowtailed fitchy cross swallowtailed quadrate cross urdy cross urdy fitchy argent crusilly of ermine spots counterchanged crusilly pointed crusilly swallowtailed crusily Celtic crusily Cerda{n~}a crux ansata crux ansata fitchy crux ansata patty crux stellata equal-armed Celtic cross equal-armed Celtic cross couped plain five lozenges conjoined in cross five mascles conjoined in cross five mascles, conjoined in cross Four compass stars conjoined in cross four ermine spots in cross four ermine spots in cross bases to center four lozenges conjoined in cross four mascles conjoined in cross, pommetty at all joints four seebl{a:}tter in cross, points conjoined Latin cross of bones Latin cross of six annulets interlaced Latin cross pointed Latin cross raguly Latin cross swallowtailed Latinate Celtic cross long Celtic cross long cross barby nowy Non cross rogacina crossed and fourchy Saint Brigid's cross San Damiano crucifix St. Brigid's crosses star cross straight-armed St. Brigid's cross swallowtailed cross Three nails bound into the shape of a cross, one palewise, the others fesswise, points to center Two cartouches voided and interlaced in cross two links of chain fretted in cross Ukrainian sun-cross

plain_cross

an orb cross cross couped cross couped and fitchy cross couped and pierced cross couped and quarter-pierced cross couped disjointed cross couped fitchy cross couped parted and fretted cross couped quarter-pierced cross couped quarter-pierced cross couped triply parted cross fitchy cross humetty cross issuant to chief cross nowy couped cross quadrate parted and fretted cross triple-parted and fretted cross voided crusilly couped crusilly Latin crusilly plain crusily Latin Greek cross Latin cross Latin cross fitchy Latin cross inverted Latin cross nowy pierced Latin cross voided long cross Passion cross the George Cross the Union flag

pomelly

equal-armed celtic cross pommety cross pomelly fitchy cross pomelly crosses pommy crusilly pommety cross bourdonny crusilly Latin pomelly cross pommetty Latin cross pometty cross doubly pommeled Latin cross pomelly at the foot cross pommy fitchy cross clechy pommetty

potent

cross potent cross of Jerusalem Jerusalem Cross long cross potent equal-armed Celtic cross potent crusilly potent Cross of Jerusalem cross gammadion saltirewise cross potenty - yes, I looked at the picture crosslet potent Latin cross potent nowy quadrate cross potent (later floretty) Latin cross potent latin crosses potent equal-armed Celtic cross potent cross potent fitchy cross potent rebated

tau

tau cross Tau cross cross of St. Antony cross tau Tau cross swallowtailed

toulouse

Latin cross of Toulouse key cross cross of Toulouse key cross nowy pierced