Guido Reni

Bears unidentified cartouche (L.3000) on the backing, with pen inscription: Carlo Cignani inv^tfecit, and again in the same hand, lower right: Carlo Cignani inv^tfecit/du Cabinet du Gouverneur...;
Carlo Prayer (L.2044); 
Juan and Felix Bernasconi, 1977 (inscription on the backing);
sale, New York, Christie's, 12 January 1988, lot 25;
sale, London, Sotheby's, 5 July 2006, lot 58

Unframed. Laid down on the remains of the previous mount, which includes a slightly damaged black framing line. In general the condition is reasonably good. There is some light surface dirt, and some slight rubbing in the area of the Sibyl's right foot. Pen and ink and red chalk strong and vibrant.
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NOTWITHSTANDING THIS REPORT OR ANY DISCUSSIONS CONCERNING A LOT, ALL LOTS ARE OFFERED AND SOLD AS IS" IN ACCORDANCE WITH THE CONDITIONS OF BUSINESS PRINTED IN THE SALE CATALOGUE."

When this drawing was on the London art market in 1988, Stephen Pepper suggested that it was an early work by Guido Reni.  Nicholas Turner, at the time of the sale in 2006, confirmed the attribution and suggested a date around 1630. 

He has also pointed out that it is related to a woodcut after Reni by the Bolognese Bartolomeo Coriolano (circa 1599?-1676).  Coriolano was trained as a woodcutter by his father Cristoforo, a German who settled in Italy in the late 16th century.  Bartolomeo probably joined Reni's studio early in his career, as Henrietta McBurney and Nicholas Turner point out in their article: 'Drawings by Guido Reni for woodcuts by Bartolomeo Coriolano'.¹  Bartolomeo's earliest documented work after Reni seems to be the chiaroscuro woodcut Peace and Abundance, dated Rome 1627.  The characteristics of Reni's drawings for Coriolano's woodcuts, as defined by McBurney and Turner, are all apparent in the present study: the boldness of touch resulting from the use of a reed pen (probably chosen to approximate the effect of the lines of the woodcuts);  the broken lines to indicate highlights;  the shading in blocks of parallel lines, cross-hatched to indicate greater shadows (and in some cases, as here, even surrounding parts of the figure to enhance the effect).

An outline drawing in pen and ink of a Sibyl, accepted by Otto Kurz as a sketch by Reni preparatory for the Coriolano woodcut, is in the Royal Collection, Windsor.²  Our study must precede the Windsor drawing, which shows the Sibyl in the same pose and in the same direction as in the woodcut, but without the winged putto.  The very lively red chalk underdrawing makes the present work rather more vibrant and interesting than Reni's other known drawings for woodcuts by Coriolano.

1.  Print Quarterly, Vol. V, No. 3, September 1988, pp. 147-242 
2.  Ibid, pp. 231-2, reproduced fig. 151