Copper(I) oxide (CAS 1317-39-1): storage and disposal

Because the label difference between the two copper oxides is a single numeral, keep them on separate shelves or in clearly separated trays. The jar belongs in a dry, labelled general store, dated on arrival and away from food grade supplies. The classification includes serious eye damage and harm if inhaled, so a fine powder that puffs out on opening needs a tight lid and a jar with a clean neck. Part-used jars from practicals should return to the shelf closed, not stay in a class set.

Look at the colour. Fresh copper(I) oxide is red to red-brown, and in air it can darken slowly towards black as it takes up more oxygen, so a jar whose powder has turned patchy or dark is no longer what the label says. Clumping points to damp. Red dust around the lid, a label that has faded and an unknown date of receipt are common. A jar that has changed colour is described as it is, and not as fresh stock, and must not be mixed back with clean powder or poured into a neighbouring jar to tidy a shelf.

We arrange this by specialist collection. We do not publish a drain or general waste route for any chemical. It is normally packed in a general laboratory pack with compatible chemicals.

The colour change makes description difficult: a jar labelled copper(I) oxide that has gone dark is partly something else, and the collection team should be told. Describe each jar by form and condition, and keep the red and black oxides apart. It is classified as very toxic to aquatic life, so it must not go down a sink or drain, into general waste or into a skip, and nobody should try to treat it first. Collection is by specialist route as hazardous waste, normally with 16 05 06* in a lab pack and 16 05 07* outside one, though the producer classifies the waste.

Usually held as: powder.

Tell us the container size and how many you hold. An estimate is enough to start with, and some items cannot be priced until someone has looked at them.