Changing the color of a brick?

So, I'm trying to get this to work and I cannot. When I click on the ClickDetector, I want the lampshade to change color, Gold in this case. This message appears and I cannot work out how to fix it. "Workspace.Part.Script:2: attempt to call field 'Gold' (a nil value)". I apologize for this question as I am quite new to scripting.

script.Parent.ClickDetector.MouseClick:connect(function()
game.Workspace.lamp1.lampshade1.BrickColor = BrickColor.Gold()
end)

BrickColor = BrickColor.new("Gold")