startup.lua

function progress()
    solid, block = turtle.inspect()
    if solid then
        turtle.turnLeft()
    else
        turtle.forward()
    end
end

function conditionalBreak()
    solid, block = turtle.inspectDown()
    if block.name == "ae2:quartz_cluster" then
        turtle.digDown()
    end
end

turtle.refuel()

while true do
    progress()
    conditionalBreak()
    sleep(2)
end