Geologo

WOX II Project – La Quinua Sur Robust Lower Part
July, 2012

GEO.S2.030 Stage 2 La Quinua Sur Robust Lower Part (LQSR) Geologic Classification of Deposit

La Quinua project is a bigunconsolidated aluvio-glacial gold deposit within Yanacocha gold district. La Quinua is divided in three zones called Norte, Central and Sur. La Quinua Sur Robust (LQSR) is part of a Quinua Sur deposit locatedtowards east and southwest from La Quinua Sur. La Quinua Sur Robust is divided in two zones, La Quinua Sur Robust Lower Part and La Quinua Sur Robust Upper Part. (See figure 1).

La Quinua golddeposit was derived from erosion, transportation, and deposition of gold particles and mineralized clasts from the Yanacocha Sur and Yanacocha Oeste deposits. However, a portion of the gold may haveresulted from chemical mobilization and reprecipitation. Gold particles are mostly micron sized, liberated within mud matrix, and disseminated within mineralized clasts; although liberated particlesto 0.2 mm have been observed. Gold is disseminated throughout the deposit with only gradual lateral and vertical grade transitions. (Mallette, P., 2004).

LQSR Lower Part project contains 178,000gold ounces and represents an opportunity to add 134,000 recoverable gold ounces to the Yanacocha district.


Figure 1: La Quinua Sur Robust Lower Part location map.
1. Stratigraphy
La Quinua Surclastic sediments as a whole represent a first order depositional sequence. Two internal second-order depositional sequences are recognized and are referred to herein as upper- and lower-sequencegravels. Both resulted from rapid sediment production in adjacent highlands and rapid influx to depositional basins in relatively high energy environments. The second-order depositional sequences arebounded by horizons reflecting lower energy and/or lower sediment-flux environments consisting of (1) basal regolith overlying bedrock, (2) organic and authigenic iron deposits separating upper- and...