North Whitemud River Resource
During Ironstone’s 2008 drilling program, 15 holes were drilled south of Rambling Creek in the block named North Whitemud River. These drill hole cores demonstrate the continuity of the deposit with ore of the same general lithological and mineral character as that found in the Rambling Creek area.
The North Whitemud River block lies between the Notikewin Road to the east and the Iron Haul Road to the west, in a broad valley. Featuring a relatively low stripping ratio of 6:1, the overlying soft, clay-rich glacial overburden measures an average thickness of 60m.
In late March 2011, Ironstone completed its second drilling program on the North Whitemud River block, drilling and diamond coring 148 holes. The ironstone deposit on this block has an average thickness of 9.5m, up to 2 metres thicker than on the Rambling Creek block.
Two mineralized zones were modelled; a densely oolitic (DIOS) and a moderately oolitic (MIOS) zone. Mineral resources were estimated using block model method with values interpolated into 50m by 50m by 2m blocks to reflect drill spacing and the relative thin nature of the deposit when compared to its lateral extent.
In order to validate the reasonable prospect test, SRK applied a Whittle shell to the combined Rambling Creek – North Whitemud River deposit to determine the amount of iron that could potentially be mined under reasonable assumptions.
Mineral Resource Statement*
Clear Hills Deposit, Alberta, SRK Consulting (Canada) Inc., November, 2011
SRK notes that “the oolitic ironstone at North Whitemud River is laterally very extensive and that the mineral resources presented in this report only represent a portion of the overall iron deposit. The deposit is open to the west, south and east and potential to expand the mineral resources in these directions is good. The deposit appears to be of consistent thickness and grade and it is reasonable to assume that additional drilling will identify additional resources”.
Vanadium is of particular interest as a co-product in a Clear Hills iron mine, with an average concentration of 0.20% V205 within the whole rock.
The Clear Hills now contain the largest compliant Vanadium resource in North America, with an in-place indicated resource of 2,454 million pounds of V205.
Note: Although SRK notes that the Clear Hills ironstone deposit is associated with appreciable concentration of vanadium pentoxide, SRK has not included the vanadium in the economic parameters while estimating the viability of the Whittle shell.
Hamilton (1980) roughly outlined the “Whitemud River” block, which encompasses the area that was drilled in 2011, and contains 620m tons of iron ore “reserves”, a historical term used at the time to describe the iron deposit which is not compliant with current NI 43-101 standards. Ironstone plans to do additional drilling over the North and South Whitemud River blocks to bring more of the deposit into compliance.