From correspondence between Benozzo and Piero de'Medici, it is known that Piero objected to the angels in the apse. Robert Martelli, a friend and confidant of Piero, was called upon to resolve the issue.
The altarpiece is a workshop copy of the original by Filippo Lippi, which was sold by the Riccardis.

Signed below the Virgin: MARGARIT[US] DE ARITIO ME FECIT (Margarito of Arezzo made me).
The narrative scenes are inscribed:

1. DE PARTV VIRGINIS MARIE & ADNV[N]TIATIO[N]E PASTORVM
   (On the childbirth of the Virgin Mary (i.e. the Nativity) and the Annunciation to the shepherds)
2. HIC BEAT[US] JOH[ANN]ES EV[AN]G[ELISTA] A FERVORE OLEI LIBERATVR
   (Here Blessed John the Evangelist is rescued from the heat of the oil)
3. HI[C] S[AN]C[TU]S JOH[ANN]ES EV[AN]G[ELISTA] SVSCITAT DELVSIANAM
   (Here Saint John the Evangelist raises Druisiana)
4. HI[C] .S[ANCTUS] B[E]NEDICT(US) P[RO]IECIT SE I[N] SPINAS FVGIE[N]S DIABOLI TE[N]TATIOE(M)
   (Here Saint Benedict flings himself among thorns fleeing the temptation of the devil)
5. HI[C] S[AN]C[T]A CATTARINA SVSCEPIT MA(R)TIRIV[M] & I[N] MO[N]TE(M) SINJ AB A[N]G[E]LIS E[ST] D(E)LATA
   (Here Saint Catherine undergoes martyrdom and is transported by angels to Mount Sinai)
6. HI[C] S[AN]C[TU]S NICOLAVS PRECEPIT NAVTIS VT VAS COL/TVM A DIABULO I[N] MARI P[RO]ICERE[N]T
   (Here Saint Nicholas instructs the sailors to throw into the sea the jar filled by the devil)
7. HI[C] S[AN]C[TU]S NICOLAVS LIBERAT CO[N]DE[M]NATOS
   (Here Saint Nicholas frees the condemned men)
8. HI[C] S[AN]C[T]A MARGARITA ... ORE ERVPTIS/ VISCERIBVS ...
   (Here Saint Margaret ... in the mouth [of the dragon, escapes] when his entrails burst)

In the centre are the Virgin and Christ Child. The Virgin wears a Byzantine crown and is seated on a lion-headed throne. Angels swing censers on either side; outside the mandorla which contains this group are the symbols of the evangelists and the eight scenes from lives of the saints described in the inscriptions.
The prominent inclusion of Saints John the Evangelist and Nicholas suggests that it originally stood on an altar dedicated to these saints.
The iconography of the Virgin and Child is very similar to that of the Virgin and Child from S. Maria, Montelungo, near Arezzo and the Virgin and Child in the National Gallery of Art, Washington, both of which bear the same signature.

The Child places the ring on the finger of St Catherine, watched by the saints.
It was commissioned for the Isolani family chapel in San Domenico.

Commissioned in 1383 by the Compagnia di S Pietro for the Annunziata Chapel in San Francesco, Montalcino.
Bartolo's style is close to that of the late work of Simone Martini. His visionary effects fulfilled the requirements of the commission, for devotion to the Virgin as Queen of Heaven occupied a central role in the liturgical life of the patrons.
The second crown, resting on the knees of the Virgin and Christ, is a feature on which you are asked to comment.
A354 1:114-116 2:206-208 Plate B:7

Detached fresco. An unusual representation of the young Virgin.

The Virgin Mary (in profile) appears to be sewing and this is confirmed by a version of this composition (Paris, Petit Palais) in which her needle and thread are visible.
The Christ Child holds an olive branch, sceptre and orb, to symbolise his role of Prince of Peace and Saviour of the World. Saint Joseph appears on his left and the young Baptist on his right.
The subject matter and composition are unusual.

The Poor Clares were the followers of Saint Clare of Assisi who established an order of nuns who followed the rule of Saint Francis.
This fragment was probably once part of a large fresco in the Chapter House of the church of S. Francesco, Siena. The original scene showed The Body of Saint Francis halted at S. Damiano and mourned by Saint Clare and her Companions.

Christ stands within the tomb before the cross. Two angels with censers are depicted at either side of his head.
This representation derives from the legend of Cristo di San Gregorio, according to which Christ appeared to Saint Gregory the Great at Mass in S. Croce in Gerusalemme, Rome.
The prototype in the church was engraved by Israel von Meckenem, and essentially corresponds with this work.

Wall sculpture of polychromed wood.