AV6 Kimberlite Body Grades 0.97 Carats Per Tonne at Aviat

06/21/2006

Stornoway Diamond Corporation (TSX:SWY), BHP Billiton and Hunter Exploration Group are pleased to report a diamond sample grade of 0.97 carats per tonne for the AV6 kimberlite body on the Aviat Project, based on the processing of 2.1 tonnes of material for diamonds greater than 0.85mm using a square mesh sieve.

The Aviat Project is a joint venture between Stornoway Diamond Corporation (70%), BHP Billiton (20%) and Hunter Exploration Group and occupies close to 4 million acres in eastern Nunavut on the Melville Peninsula, north of Hudson Bay.

Dense Media Separation (DMS) processing of 2,149 kilograms of kimberlite collected from surface exposures of the AV6 kimberlite in the fall of 2005 yielded 2.0805 carats of diamonds recovered on a 0.85mm square mesh screen, for a grade of 0.9681 carats per dry tonne. The majority of the diamonds are described as bright white stones representing a mix of octahedral and tetrahexahedroid forms. Stone counts for standard sieve categories are provided below:

Sample

Sample Weight

Sieve Size

kg (dry)

0.85mm

1.18mm

1.70mm

2.36mm

AV6 Hypabyssal Kimberlite

2149

66

23

8

1

A single stone recovered on the 2.36mm sieve weighted 0.1025 carats. The eight stones recovered on the 1.70mm sieve collectively weighted 0.5775 carats. Click here to view a slideshow of the nine largest stones.

As previously reported (see press release dated Sept 21, 2005), subcrop of the AV6 hypabyssal kimberlite is located approximately 2.5 km southeast of AV-1 and is exposed over an area of approximately 3m by 17m as determined by hand dug surface test pits. Two drillholes testing the body in 2005 intersected multiple short intersections up to 0.9 m in length, but the shape and extent of the body remain poorly understood and it has not yet been adequately delineated from drilling. Prioritization of this work is pending diamond results from this 2.1 tonne sample as well as DMS results for the remaining 1.5 to 2.5 tonne kimberlite samples collected from six other Aviat kimberlites (AV2 to AV5, AV7 and AV8).

Eira Thomas, President and CEO commented: "AV6 is located 2.5 km southeast and directly on strike from AV1 and appears remarkably similar in terms of its diamond content. Our present understanding from both the microdiamond work and now from the recovery of larger stones using dense media separation, continues to suggest that the Aviat bodies discovered thus far are all related, and likely part of a single intrusive event which exploited a northwest-southeast trending structural feature over strike length of more than ten kilometers. With further work, we believe significant tonnage potential could be achieved within this corridor."

Diamond results reported above are based on recovery of diamonds by a Dense Media Separation (DMS) plant owned by Stornoway, and operated by Microlithics Laboratories, Thunder Bay, Ontario, an independent mineral process laboratory currently providing services exclusively to Stornoway and its affiliates. The DMS plant was purchased new and delivered in November of 2005. After extensive debugging, upgrading and rigorous real life testing (including processing of archived AV1 kimberlite material with a diamond grade known from comparative third party DMS work) the plant has been successfully commissioned and will be used by Stornoway to assess and evaluate diamond exploration properties in our extensive portfolio.

Stornoway is one of Canada's premier diamond exploration companies with extensive landholdings (approximately 18 million acres) focused in key project areas in northern Canada and Botswana. Stornoway has been involved in the discovery of 61 kimberlites since 2002, 30 of which have proven diamondiferous.

Stornoway's diamond exploration programs are conducted under the direction of Robin Hopkins, P.Geol. (NT/NU), a Qualified Person under NI 43-101.

On behalf of the Board
STORNOWAY DIAMOND CORPORATION
/s/ "Eira Thomas"
Eira Thomas