To the left I have included a terribly small photo of the first work, Exhaled Cocaine by Cornelia Parker. Her piece is on the pedestal toward the back of the room. I couldn't find a better photo than this, but I will soon upload a close-up of it taken from one of my Matthew Collings books, where I first saw the piece.
"For ‘Exhaled Cocaine’ Parker persuaded Customs & Excise to give her the ashes of seized, incinerated cocaine, presented by the artist as an end product ‘breathed out’ by a crucial process in its history."
Of course, you can't really "exhale" the substance, but you can burn it, which destroys and purifies, but also recalls the process in which it was made- using flammable materials like kerosene on coca leaves. So, the work acts as a cyclical tableau.
The second work (shown above) is Cocaine Buffet by Rob Pruitt, which consists of a pile and long line of cocaine offered up on mirrors lining the floor of an artist studio like a two-dimensional Rube Goldberg device. Participants were invited to "engage" with the work, which they eagerly did. Lygia Clark, eat your heart out.