This may be off topic since the pill is identified, but it's best to be aware of the entire situation.
Darvocet is a very common pain pill made by many manufacturers.
And I find this interesting:
"The UK last year started a phased withdrawal of all
propoxyphene containing products from the market. And recently Public Citizen, a non-profit consumer advocacy organization, petitioned the Food and Drug Administration to withdraw propoxyphene products from the US market."
http://www.citizen.org/publications/release.cfm?ID=7420
I'm not a pharmacist or a medical doctor. This message is not medical advice nor is it an offer to provide medical advice. All drug identifications should be validated by a licensed MD or pharmacist.