Here is the official Case description of that particular run of knives (assuming yours was made in 2004). They called it "Standard Jigged Black Bone."
Here is the information on the Case/Ruger Knives:
* 06500 - Nov. 2004 - Standard Jigged Black Bone Gunstock 6215 SS - Red Ruger Shield - Package in Rugger Tin w/pouch
* 06501 - Nov. 2004 - Standard Jigged Black Bone Gunstock 62130 SS - Red Ruger Shield - Package in Rugger Tin w/pouch
* 06502 - Nov. 2004 - Standard Jigged Black Bone Cheetah 6111 1/2L SS - Red Ruger Shield - Package in Rugger Tin w/pouch
* 06503 - Nov. 2004 - Standard Jigged Black Bone Trapper 6254 SS - Red Ruger Shield - Package in Rugger Tin w/pouch
* 06504 - Nov. 2004 - Standard Jigged Black Bone Stockman 6318 SS - Red Ruger Shield - Package in Rugger Tin w/pouch
* 06505 - Nov. 2004 - Standard Jigged Black Bone Peanut 6220 SS - Red Ruger Shield - Package in Rugger Tin w/pouch
* 06506 - Nov. 2004 - Standard Jigged Black Bone Mid-Folding Hunter 61265LC SS - Red Ruger Shield - Package in Rugger Tin w/pouch
* 06507 - Nov. 2004 - Standard Jigged Black Bone RussLock 61953L SS - Red Ruger Shield - Package in Rugger Tin w/pouch
* 06508 - Nov. 2004 - Ruger Founder Knife - Peach Seed Jigged Burnt Honey Bone Bone Large Gunstock 62130 SS - Silver Ruger Shield - Tech print in black on main blade w/Ruger signature - Tech print in black on secondary blade with Sturm signature - Scrolled cap bolster - Packaged in wooden box with Case/Ruger medallion
* 06509 - Nov. 2004 - Peach Seed Jigged Burnt Honey Bone Trapper 6254 SS - SSM polished blades - SR scrolled bolsters - Silver Ruger Shield - Tech print in black on ms clip blade w/Ruger signature - Tech print in black on ps spey blade w/Sturm signature - - Package in Original Ruger Factory tin with w/deck/Case/Ruger Medallion.
This is from a 2004 post on Knifeforums by Shirley Boser, the Case Historian at the time.
http://www.knifeforums.com/forums/showpost.php?post/488169/
You can contact Case and talk to or e-mail Katie Shonts-Saar. She is the current Case Historian and can probably help you definitively identify your knife.