Prosecutors on Friday showed a court written proposals for antiquities they contend bolster their case that a former Getty museum curator knew that the artifacts were being illegally acquired.

Thank-you letters and even an apology were also among the correspondence that Prosecutor Paolo Ferri displayed to the court in Rome where Marion True, an American who was antiquities curator at the J.Paul Getty Museum in California, and Robert Hecht, an American art dealer, are on trial.

Ferri contended that that the correspondence is evidence that True made numerous deals with Giacomo Medici, an Italian art dealer who was convicted in Rome a year ago of conspiring to deal in illegally acquired antiquities.

True and Hecht are accused of receiving and conspiring to deal in illegally acquired antiquities. The defendants have denied any wrongdoing.

One of the letters shown to the court was an apology from True to Medici, in 1987, for a decision by the Getty not to buy a batch of 20 Etruscan ceramic plates.

"I do hope that you understand that the decision was not mine," read the letter that the prosecutor said was sent from True to Medici.

Ferri told reporters after the session that the apology was evidence of the extensive dealings between the two.

In one letter cited by Mr. Pellegrini, Ms. True thanks Mr. Medici for donating the head of a kouros (a statue representing youth) to the Getty, and for providing information on the provenance of three fragmentary proto-Corinthian olpai, or pitchers, in the museum's collection. Ms. True wrote that it was "helpful" to know that the pieces "came from Cerveteri and the area of Monte Abatone," an area in central Italy rich in archaeological sites. "The fact that Medici was able to be so specific about the provenance of the pieces means he's been in contact with the robbers who raided the tomb," the prosecutor, Paolo Ferri, said. "And it shows that True knows of these contacts."