If you mean income inequality, I don't think that is correct.
I mean relative to Argentina and Uruguay, countries with relatively similar standards of living and historical development. Comparing Chile's economic and social development to Bolivia wouldn't really make much sense.
Chile doesn't have the ethnic divide and regional development issues countries with higher GINI coefficients do in the region, like Brazil, Colombia, Paraguay, and Bolivia.
To be fair both Chile and Venezuela have benefited of the rising prices of oil and copper in the international markets. The oil price has tripled since the invasion of Iraq and copper quadrupled.
This is true, and both countries have used their resources to achieve different things. But only Chavez was criticized for relying on resource extraction - to take people out of poverty.
You have to remember when comparing Uruguay to Chile or Argentina, it's like comparing Germany to Denmark. A country of one tenth the population is bound to have smaller class and income differences, greater stability and predictable politics. There may even be regions of Chile with comparable size and GINI coefficients to the whole of Uruguay. It's not always the politics that governs wealth distribution.
Chile and Uruguay have a relatively similar population distribution - both have similar population densities (19 per sq km for Uruguay, 22 for Chile), a third of both countries live within the prosperous capital metropolitan area, while the rest of both countries are relatively underpopulated. If anything the outer regions of Chile are more prosperous and equal, since they have low populations and plenty of natural resources.
So no, in the case of Chile, their GINI coefficient is directly a result of policy.