The Follis denomination
The follis was originally a large bronze coin with around 5% silver content introduced at the time of the coinage reform of Diocletian. It weighed about 10 grams.

Due to rampant inflation, the follis was quickly reduced in weight and by the time of Constantine it was a shadow of its former self and barely contained any silver at all.

The follis was reintroduced as a large bronze coin (40 nummi) in 498, with the coinage reform of Anastasius.
Follis
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An AE Follis struck 491-518 AD in Constantinopolis
Obverse:

Reverse:

Diameter: 38 mm
Die Orientation: -
Weight: 17.25 g
No notes for this coin
No references provided for this coin
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An AE Follis struck 1025-1028 in Constantinopolis
Obverse: + ЄMMΛ-HOVHΛ, barred IC XC across field, nimbate bust of Christ facing, holding Gospels

Reverse: + IhSЧS/XRISTЧS/bASILЄЧ/bASILЄ· in four lines across field; above and below; ornate As.

Diameter: 29 mm
Die Orientation: -
Weight: 8.29 g
Anonymous, but attributed to Constantine VIII
DOC class A2; SB 1818
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An AE Follis struck 624-625 AD in Thessalonica
Obverse: Martina (his wife) on left, Heraclius in center and Heraclius Constantine (his son) on right, standing facing, all crowned and wearing chlamys and all holding cross on globe

Reverse: Large M, ANNO at left, cross at top, B below, XVI at right, ΘEC in exergue

Diameter: 23 mm
Die Orientation: 7 H
Weight: 3.42 g

Byzantine Empire
Heraclius regnal year 16 = 624-625 AD
Second officina in Thessalonica mint

Sear 825
(4) Leo VI
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An AE Follis struck 886-912 in Constantinopolis
Obverse: +LЄOҺ bAS-ILЄVS Rom. Crowned and draped bust facing, holding akakia.

Reverse: +LЄOҺ/ЄҺ ӨЄO ЬA/SILЄVS R/OmЄOҺ in four lines.

Diameter: 25 mm
Die Orientation: -
Weight: 3.86 g
No notes for this coin
DOC 8; SB 1729
(5) Leo VI
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An AE Follis struck 886-912 in Constantinopolis
Obverse: +LEON bAS-ILEVS ROM, crowned bust facing with short beard, wearing chlamys, holding akakia

Reverse: +LEOh Eh ΘEO bA-SILEVS R-OMEOh, legend in four lines.

Diameter: 23 mm
Die Orientation: -
Weight: 5.58 g
No notes for this coin
Sear 1729; DOC 8
(6) Leo VI
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An AE Follis struck 886 - 912 AD in Constantinople
Obverse: +LEON bAS-ILEVS ROM / crowned bust facing with short beard, wearing chlamys, holding akakia

Reverse: +LEOh Eh ΘEO bA-SILEVS R-OMEOh / legend in four lines

Diameter: -
Die Orientation: -
Weight: 7.87 g
No notes for this coin
Sear 1729
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An AE Follis struck 601-602 A.D. in Theopolis
Obverse: DN MAV G I CN P AVG - Crowned and mantled bust facing, trefoil on crown, holding mappa and eagle-tipped sceptre.

Reverse: Large M, ANNO to left, cross above, regnal year XX (20) right, officina letter Δ below. Mintmark THEUP'.

Diameter: 28.7 mm
Die Orientation: 12 H
Weight: 10.54 g
No notes for this coin
SB 533.
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An AE Follis struck 1068-1071 A.D. in Constantinople
Obverse: IC-XC - Bust of Christ facing with nimbate cross, pallium and colobium, and raising right hand in benediction, scroll in left hand.

Reverse: MP-OV - Facing bust of the Virgin Mary, nimbate and wearing pallium and maphorium.

Diameter: 27.4 mm
Die Orientation: 6 H
Weight: 6.39 g
Romanos IV, Class G Anonymous Follis overstruck on a Constantine X Follis.
SB 1854 (Constantine X).
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An AE Follis struck 527 in Antioch
Obverse: Cuirassed bust right with text DIИIƧIΓΛNOVƧ

Reverse: Large M Star both sides, cross above, no officina letter present, mint mark ANTIX

Diameter: 31 mm
Die Orientation: -
Weight: 14.3 g
No notes for this coin
Sear 213 Prototype?