The Schaefer die study pages were added not long ago to the Coinage of the Roman Republic Online.Over about 25 years, Richard Schaefer collected images of ~300,000 Roman Republican denarii ordered by Crawford numbers documenting unique dies and links between dies.It is an amazing resource - here's a reduced image of one page from the notebooks that are now online. For more information on this database there is an excellent ANS blog entry by Lucia Carbone.
I have been periodically looking up coins from my collection to see if I can find a die match in the Schaefer notebooks. Doing so today with my coin of Crawford 426/2, I had a pleasant surprise. My coin is pictured on page for 426/2 shown above, adding provenance to my coin from "Feb 95 / WP / 138".
The banker's mark on Hercules' cheek makes it easy to recognize this coin. There is a second example of the same die (F) so that I can see the star above the horses that is off flan (or very weakly struck) on my coin. Thanks to a set of notes from Liv Mariah Yarrow, I can identify the WP and Wayne C. Phillips and I now know where this coin was in Feb 1995. This ad from the February 1995 issue of the Celator is helpful.
Here's my photo of the coin today:
Faustus Cornelius Sulla, Rome, 56 BC, AR Denarius
Obv: FEELIX, diademed bust of young Hercules right, wearing lion skin headdress
Rev: FAVSTVS, Diana driving galloping biga right, holding reins and lituus; crescent above her head; one star above, two stars below horses
Ref: Crawford 426/2
Note: die F on R. Schaefer die project notebook (this coin pictured from Wayne Phillips Feb 1995)
This coin a difficult one to find with <30 dies reported in Crawford and particularly interesting to me as the obverse of Hercules could also be intended to show Lucius Cornelius Sulla on this coin from his son, with Caecillia Metella, Faustus Cornelius Sulla the moneyer.
Faustus was married to Pompeia the daughter of Pompei the Great and sided with his father-in-law during the civil war between Caesar and Pompey. After the battle of Thapsus (in modern Tunisia) he was killed by Publius Sittius, a supporter of Caesar in 46 BC. At least two children with Pompeia are known, one of whom had a descendant who became a senator and consul suffectus (elected under circumstances where the consul died or was removed from office) under Tiberius in 31 AD.
For another recent find with surprise provenance from the Richard Schaefer die notebooks see this post: Unencrypting Crawford RRC