Here is mine, still traveling so no data but its pretty.

Any ideas? I am traveling and no access to my library. 

17/18 mm ; 5,16g

The description includes dealers hype

★ Exceptional For The Issue ★

John VIII Palaeologus. AR Half Stavraton (3.3 gr.), 1425-1448. Constantinople. Nimbate bust of Christ facing; sigla: unclear / Nimbate facing bust of John; sigla: • | •. Cf. DOC 1781; PCPC 349 (unclear sigla); LPC p. 172, 2; SB 2565.

Good Very Fine, Very exceptional for the issue. One of the very finest known examples of this very hard issue

And of course a full example 

John VIII SBCV-2564 7.14gm 1425-1428 AD

Silver stavraton, cf. DOC V 1277 (also no sigla) & 1295 - 7 (similar rev.); Bendall LPC p. 154, 2; Lianta 900, Bendall PCPC 327, SBCV 2510, aVF, toned, die wear, obverse die crack (line below chin), flan cracks, legend not fully struck, 7.911g, 26.9mm, 180^o, Constantinopolis (Istanbul, Turkey) mint, phase VI, 1379 - 16 Feb 1391 A.D.; obverse bust of Christ facing, bearded, nimbate, wearing tunic and kolobion, IC - XC (Greek abbreviation: Ihsoús Xristós - Jesus Christ) flanking over Christ's shoulders, eight stars alternating with eight pellets in outer circle, no sigla; reverse + IW ΔECΠOTHC KAI AVTOKPATOP AVG / + ΘVXAPITH BACIIΛ TWN PWMEWN (or similar, blundered, partly unstruck/off flan)), facing bust of John V, bearded, nimbate, wearing domed crown with pendilia, and maniakon, no sigla; from the Robert Wachter Collection; very rare

Here are my two examples of Islamic Anonymous follis, I would cross Islamic off the list for your coin. 

Your reverse seems to be Greek ( Upside-down?)

19 minutes ago, Valentinian said:

It is not easy to get a well-struck trachy of Michael VIII. 

Your right there, I have many trachea from this time period not fully attributed but this is one of my favorites, poorly struck but still nicely done. 

Nice dark coin, good portrait of emperor. 

I picked this  Gepids example from Forum Ancient Coins a few years back. Not the same coin but authentic, it gives you an idea.

Kingdom of the Gepids, Thrasaric, c. 491 - 504 A.D., In the Name of Anastasius and Theodoric the Great

 Silver quarter siliqua, Demo 77 var. (legend variations), VF+, centered, toned, edge bend, edge chips, Sirmium (Sremska Mitrovica, Serbia) mint, weight 0.820g, maximum diameter 16.2mm, die axis 180^o, c. 491 - 504 A.D.; obverse D N ANASTASIVS P AV (N's inverted, A's appearing as Λ), diademed and cuirassed bust of Anastasius right; reverse * V INVICTA + A ROMANI (first N inverted, A's appearing as Λ),  monogram of Theodoric, cross above, star below; ex Roma Numismatic

Theodore II Ducas-Lascaris ( 1254-1258)

SBCV-2143 29mm  3.9gm 

And a coin that is a bit more common but not in this condition. This type of coin was included in Wayne Sayles Masterpieces of Romaion Coinage.

John III  tetarteron 

Not an easy attribution based on your photo.

The difference between two half tetarterons Of John II with St Demetrius and Manuel I with St George, besides the legends and the emperor's attire, is St George has a round shield, St Demeterius has a triangle shield, see examples bellow. 

I would say your coin is SBCV-1980 Manuel, the main reason is the attire of the emperor. I cannot tell what type of shield your coin has. 

JOHN II AE HALF TETARTERON S-1955 DOC 17 CLBC 3.4.6
OBV Bust of St. Demetrius beardless and nimbate, wearing tunic, breastplate, and saigon. Holds in r. hand sword and l. shield.

REV Bust of emperor wearing stemma, divitision, collar piece, and paneled loros of a simplified type; holds in r. hand labarum headed scepter and in l. gl. cr.

Size 16.81mm

Weight 1.9gm

And here is the coin from his son. 

MANUEL AE HALF TETARTERON S-1980 DOC 23 CLBC 4.4.9OBV Bust of St. George, beardless and nimbate, wearing tunic, breastplate, and Saigon; holds in r. hand spear, and in l. shield.

REV Bust of emperor, bearded, wearing stemma, divitision, collar piece, and jeweled loros of simplified type; holds in r. hand labarum headed scepter, and in l. Globus cruciger.

Size 17.30 mm

Weight 2.4gm
 

Beautiful collection @voulgaroktonou , it is so hard to find interesting and well struck in this series.

The denominations begin going downhill durring the reign of Alexius III , then ( or during) the introduction of the faithfull copies/Bulgarian imitations. The trachy denomination was no longer billion, not even silver coated to deceive. 

My collection Stopped at Alexius III but I have picked up some examples of Latin coinage that had some beauty to it. 

My favorite is this., Unique imagery and attractive. 

I spent twenty plus years working on my collection of the 12th century. Originally just,tetartera. Then I decided to finish the century.  Now I only buy when they are better than my examples or my new collection of assaria. 

Alexius III coinage is a real pian to collect, so many variations, the mint seemed to lose all control that was seen with the previous emperors. Even looking @Valentinian example of the tetarteron, I have never seen the ball on the middle of the labrum so bold, wonderful example. 

My collection lacks the Hyperpyron but I do have several El Aspron Trachy, again, none seem to be exactly the same, always variations.

My best portraits however are on the billion trachy. He is on the reverse on the left, the other fellow is Saint Constantine. 

Here is an awesome Half tetarteron, 

ALEXIUS III ANGELUS-COMNENUS AE HALF TETARTERON S-2016 DOC 7 CLBC 8.4.4

Size 16mm

Weight 1.7gm

coin shows. The FUN show here in Florida, is where I got this. One of the dealers had bags of the anonymous series to go through. I like this one, paid well under 100 for it assure you. Its 35mm Its condition is only fine but its still nice.

Here is the coin tray I made some time ago for Isaac II, all are included but I used a 15mm die for the half tetarteron, since then I did find a 12mm and included it bellow the tray. This with the 12mm die is a complete set for Isaac II. 

Isaac II was part of a cult that was dedicated to Archangel Michael. Thats why he is on almost all of his coinage. 

From l to r, Hyperpyron, El Aspron Trachy, Billion Trachy ( Var with Patriarchal cross.) City Tetarteron, tetarteron , Half tetarteron (15mm die but 2.2. gm)

And the 12mm tetarteron. The detail of the Archangel Michael proves to me this is an official issue, not an imitation. 15MM 1.9GM 

And last but not least, one of my favorites not pictured above. SBCV-2005 ( Same scale as 12mm die above.)

His reign does not end well, he was blinded but he does make a comeback. He will later rule with Alexius IV  ( I do not have his 2nd reign coin or Alexius IV coin.  Hope fully someone will surprise us.) 

Here is Isaac Comnenus of Cyprus, an Usurper. 

I have numerous tetartera of him but unfortunately this has his best portrait among them. His tetartera were modeled after the city tetartera and did contain 1% of silver. 

Andronicus was an evil bastard.

When Manuel Passed his teenage son took the purple with his mother as overseer. The public at the time did not care for Manuels widow a westerner, during Manuel Comnenus life he had started favoring the west, its ways , its traditions. If he had lived longer or had his son a little bit older when he took the throne, we have seen a different ending of the empire, this was one of those many what if moments in history. 

Andronicus came to the aid of Alexius II, he subdued a rebellion and vowed to protect the new emperor, instead he planned one of the most elaborate coos. He tricked the boy emperor into having his mother from the West killed, then he arranged to have the boy killed and took the thrown for himself. Andronicus was in his 70's during these events, he even took Alexius II bride as his new wife.

He removed the protection of the Latins in the city and a massacre occurred of merchants and immigrants. This resulted in a division in the two empires that would never be mended.

Andronicus was overthrown by supporters of Isaac II, he died a miserable death taking two days of mob torture.  

His gold coinage market is full of forgery's. I only need a hyperpyron to complete my collection of his rule, but I am waiting for an example reliable source.

Here is a El Aspron Trachy, the only coin I have still in a CNG slab, again I am weary of his forgeries. 

His billion trachea tend to lack the silver coating. This one has done well in time. 

ANDRONICUS Trachy SBCV-1985

Here is the nicest example of a City tetarteron I have ever seen. One of the gems in my collection. 

ANDRONICUS METROPOLITIAN TETARTERON SBCV-1986 DOC 5 CLBC 5.4.1 

Size 20.84

Weight 4.55gm

Here is one of my oldest pieces in my collection, I purchased it almost 25 years ago.

 ANDRONICUS AE TETARTERON S-1987 DOC 6 CLBC 5.4.2

Size 21.96 mm

Weight 5.1gm

Another example 

ANDRONICUS AE TETARTERON S-1987 DOC 6 CLBC 5.4.2

Size 20mm

Weight 3.63gm

This one is special, it came from the collection of Simon Bendall, it is very rare and said to only to have been minted for a month, during the siege of Thessalonica. It has been attempted to be reattributed to a later ruler but the evidence still points to Andronicus. 

Andronicus I SBCV-1988 DOC 7

2.57gm

20mm

Next is a half tetarteron but on a large flan, the die size matches the 12mm half tetarteron but the size and weight do not. So that makes this a visually great example. 

ANDRONICUS HALF TETARTERON S-1989 DOC 8 CLBC 5.4.3

Size 22 mm

Weight 3.4 gm

The Alexius coin reform was inexpensive way to start a brand-new exciting series. A new design without using more metal. 

As for the silvering, the silvered versions are out there , far scarcer than the ones without but they do exist. Here is one of the earliest in the series, I try not to touch it afraid to to lose the extra silvering.  

Alexius SBCV-1916

This one I have had the longest

John II ( Unusually heavy silver content and silvering)

Later the coins appear with less silver and by the time of Alexius III silver content had become at its lowest and the coins issued by the Latins had no silver content or any silvering. 

Nice coin @ambr0zie and welcome to a world of puzzles, the 12th century is easy, it is the 13th and 14th that are much more difficult to find in nice condition and much more difficult to attribute, you started the right way, if you dont understand the original examples of the coin reform the later ones don't make as much sense.

I know we are still on Manuel but I have Jet lag and I thought I would offer this Manuel coin that might have been used by his son Alexius II, no images on coins are known of Alexius II and it has always been assumed he continued with his fathers coinage for his short rule, he was also very young, , I think the best finds would be his father's coinage with his name. They have discovered Isaac II coins with the portrait and split beard of Andronicus. So it could be possible.

Manuel I, Comnenus (1143-1180), electrum aspron trachy, Thessalonica, Virgin enthroned facing, holding before her, nimbate head of the infant Christ facing, rev., Manuel and St. Demetrius standing facing, holding labarum between them; 1.89g (DO 9.5; S. 1974), four minor flan cracks, very fine Ex European Ambassador Collection, formed in the 1950s and 1960s.

When doing my research I ran into an article that delt with why these examples were clipped, the article was written by Robert D Leonard Jr. The article called
(99+) Andronicus Comnenus's Invasion Money of 1181-1182 | Robert Leonard - Academia.edu

It surmised that Electrum Aspron trachea from the reign of Manuel and John II had been clipped and hammered into shape to roughly half the weight of the normal denomination by Andronicus, to pay an army of mercenary's under the pretense of saving Alexius II the young ruler of the Empire from his mis deeding guardians. Andronicus successfully does take the city and becomes his new guardian. So these clipped coins were technically issued by Alexius II.

This article is an interesting theory and if true would make these clipped coins the only known coins of Alexius II.

I have been traveling for work the last month,back in forth to Seattle and Alaska thus I missed too many posting dates.

Here are two Hyperpyron by Manuel. 

Constantinople issue 

And the Thessalonica version, this one has a cert by David Sear. ( smaller die and one cross on Globe.)

Here is another favorite a Billion aspron trachy, very well struck. 

Another but this is a City tetarteron

And this one is a beautiful but off-center half tetarteron. 

Enjoyed it, wish I saw more. Congratulations @TheTrachyEnjoyer on a great presentation. 

After sourcing through several coin books of the period I finally found out where the names Stamenon and Assarion came from. The information is in Michael Hendys The Byzantine Monetary economy  300-1450 

The other books I checked ( DOC V, Bendall, Lianta and Grierson) used the names but not uniformly, and none of them mentioned the source of the names. Hendy included the information in the book. 

Stamenon  ( Stamina) was a nickname for a trachy since the time of Manuel Comnenus. It was a vulgar term but it seemed to become a popular term with the Latins and not the Greeks. Discussed in Hendy pg 514 

Assarion i( Assaria) is mentioned in the works of Byzantine mathematician but it is not clear if that was the usage name, it does appear in several documents but Hendy was not convinced that was the common name for the coin BUT he felt it acceptable to use until we knew more. 

Thank you Ross, I realize both are subpar, It is nice to see what  it should like. 

2 hours ago, Zimm said:

I believe the first coin is Sear 2377 of Andronicus II, with St. Demetrius on the obverse. I think I may see his shield near the bottom right corner of the obverse

Thank You @Zimm, I believe you are correct. I saw the shield, but I was checking Lianta, this coin had one similar LI 837 but no akaia in hand. I will try to find a match in her book too. 

3 hours ago, Zimm said:

 The second coin seems to be Sear 2440 of Andronicus II & Michael IX. You can just barely make out that the obverse is supposed to be a legend in four lines.

Thank You on this as well, I first saw a legend but when you stare at it too long it becomes a man on a horse. 

I am really started to get hooked on this series, finding nice examples is a pain. 

Best Wishes,

Simon

I am stuck on these two. 

The first I do not know if it is an assarion or a trachy/stamenon . It is slightly concaved.   , so that pointed me towards Lianta 837 but the emperor has a scroll or sword in his right hand.

This one is an Assarion, the reverse is a jumble in my eyes, joint rule but can someone see something I am not. Any help is appreciated.

Legend or mongram. I am uncertain. 

The reverse flipped. 

On 6/27/2022 at 10:18 PM, VD76 said:

 Orlyk , "Coins in Byzantine Style with the Latin Letters R-E-X " NumChronicle 181 , 2021 , PL 32 - 22( This coin ) 

This article has removed any doubts I have had on this coin, it is minted in Cyprus, it is a Crusader coin, not Byzantine. It was either done by  Richard the lion heart or and/or the Knights Templar. The two variations make perfect sense, one billion one not. The author of this paper Vasyl Orlyk did a brilliant and thorough job. DOC should update that link. 

I was perplexed over this coin to see if I needed one to complete my tetartera collection, I do not, it is not based on a Byzantine denomination, but I think it would be a real treasure to own one.  Thank you for the links @VD76 and congratulations on owning that beauty. 

Okay, I know it is rough, but I got it for a fair price and I need it for the usurper collection.  20.5mm and light at 2.56gm 

Here is what it is meant to look like.