Cathul Thuku
Admiral, Therapy Command

Image source: Jedi Apprentice: The Fight for Truth (Siri Tachi is wielding the purple-bladed lightsaber; it's the only canonical picture of her lightsaber that doesn't show it wielded with both hands)
Intent: To provide a lightsaber for Cathul found in a dig around an abandoned base on Azure
Development Thread: Destiny | Mandaorian Clans Dominion of Azure Hex (posts #13, 19, 26, 31, 38, 43, 49, 54, 59, 64)
Manufacturer: Siri Tachi
Model: N/A
Affiliation: Cathul Thuku
Modularity: No
Production: Unique
Material: Rubberized durasteel, lightsaber components
Classification: Lightsaber
Size: One-handed
Length: Hilt: 37 cm, blade: 146 cm
Weight: 4 kg
Special Features:
- 2 hurrikane crystals
- Bifurcating cyclical ignition pulse (allows the lightsaber to operate underwater)
Strengths:
- Can operate underwater
- Can cut through most materials
Weaknesses:
- Does not provide any enhancement to the Force skills of its user
- Does not deflect slugthrowers
- Will be resisted by standard lightsaber-resistant materials
Description: Its original maker and owner, Siri Tachi, was a contemporary of Obi-Wan Kenobi during his Padawan days. She was known to be highly skilled with a lightsaber and wielded a purple-bladed lightsaber containing hurrikaine crystals until her death on Azure during the Clone Wars to the hands of Magus. Magus not having any interest in Siri's lightsaber, nor did Obi-Wan or Anakin, her body was buried on Azure six feet under according to Dwartii tradition, with a coffin of a special design, where it endured the centuries forgotten by history.
Cathul undertook a dig of the abandoned Republic base after having sensed a Force-presence, while en route to Mandalore, so she decided to stop by Azure to ascertain the nature of the Force-presence on Azure. It turns out that it was the lightsaber of a Jedi knight who died during the Clone Wars She inspected and cleaned the lightsaber, revealing that the lightsaber was filthy and all of its components accumulated dirt over the centuries, but she found it otherwise rather "vanilla" compared to the other lightsabers she knew about: nothing that enhanced her power or her skills could be found in it. Nevertheless, like many lightsabers from that era and later, it had a bifurcating cyclical ignition pulse to allow underwater operation.
Primary Source: Siri Tachi (she does not have any lightsaber-specific page on Wook)
*This is a canon item*