An 18 karat gold tanzanite ring with the specified gemstones would be an exquisite piece of jewelry characterized by the following features:

1. Material: The ring is made of 18 karat gold, which means it consists of 75% pure gold mixed with other metals for strength and durability. The gold can be yellow, white, or rose, depending on the alloy used.

2. Center Stone: The focal point of the ring is a 2.25 carat emerald-cut tanzanite. Tanzanite is a rare gemstone known for its vibrant blue-violet color, and the emerald cut enhances its clarity and brilliance with rectangular facets that create a hall-of-mirrors effect.

3. Diamonds:

   • Total Carat Weight: The ring features a total of 2.05 carats of diamonds.
   • Shape and Cut: It includes small round brilliant-cut diamonds and straight baguette-cut diamonds.
   • Color: The diamonds are H color, which means they are nearly colorless and offer a good balance of quality and value.
   • Clarity: The diamonds have SI (Slightly Included) clarity, indicating that they have small inclusions that are noticeable under 10x magnification but not visible to the naked eye.

The combination of the deep blue-violet tanzanite with the sparkle of the nearly colorless round and baguette-cut diamonds set in rich 18 karat gold creates a luxurious and eye-catching ring. The different cuts and arrangements of the diamonds add both brilliance and a sophisticated design element, making this ring a stunning piece of fine jewelry.