Dealing with data

You've managed to get the best price for your phone, found a reputable site to send it to and you've got your freepost envelope ready to send it off. However there are a couple more things you need to be aware of before you ship your old mobile friend off to the suppliers.

For instance, there are some of you that might have bought the phone somewhere other than a retailer, perhaps off a friend or at a car boot sale. Therefore it's important to check the phone is legitimate first before posting, as not only will most sites not pay your should it be discovered as stolen, but some will pass your details onto the authorities too.

The good news is it's easy to check; simply go to CheckMend, which is the world's largest database of over 40 billion serial numbered items of property with information that is relevant to purchasers of used goods. For £1.99 you can check the history of any item of property including the likes of laptops, mobile phones, Sat-Navs, gaming consoles and iPods.

You'll need the phone's IMEI (International Mobile Equipment Identity) number, which can be displayed on most phones by dialling the code: *#06#. The IMEI is also usually printed on the compliance plate under the battery.

After that, make sure that you've taken out the SIM card, memory card and wiped all the data (see Wipe It Clean for more information on how to do this). After all, with all the research you've done to get the best price, you don't want to give a little extra gift of all your text messages, numbers and photos from the last couple of years...

Wipe it clean

If you're looking to get rid of your phone, then you'll need to make sure that you've got rid of any personal data such as messages, contacts or photos.

Simply going through and deleting might do the trick but there's always a chance you've missed something, like your internet browsing history or email passwords.

For some devices, it's a simple process. For instance with Android phones, you can simply browse to privacy settings, click 'Factory Data Reset' and the phone will completely wipe itself.

For Nokia phones, most of the time you can completely eradicate data by tapping *#7370#, or with the iPhone it's a simple case of connecting it up to iTunes and following the on screen prompts.

Mazuma Mobile offers a data delete tool for hundreds of mobile phones, giving you a step by step guide to removing data on your phone via email. It's a simple and free service, offering elements ranging from 'secret' codes that will wipe your phone, guiding you through the menu to the reset function or even which buttons to hold down to automatically reset your handset.

And don't forget to back up your data – in most cases you should install the bundled software that came with your phone (such as Nokia PC Suite, Samsung New PC Studio iTunes for Apple iPhone) and follow the on-screen instructions to backing up photos and contacts. Messages are harder to save, but many smartphones now offer that functionality too when connected to a PC or Mac.

What inside a phone can be recycled?

Screen - The LCD inside a phone (up to 10% of the construction) currently cannot be recycled as a separate part, so has to be ground up and metals extracted from within it. However, researchers hope in the near future the liquid crystals used in these displays can be harvested to save money and waste.

Battery – Mobile phone batteries contain a number of harmful materials, and are one the most important elements to dispose of safely. Cadmium, lead and mercury all will dissipate into the soil when used for landfill putting the local environment at risk, but can be recovered to make new batteries.

Casing – Mobile phone casing is mostly plastic, making up 30% of the phone. While this cannot be easily recycled (due to a large amount of glues and other epoxies present) it can be melted down and used for things like traffic cones and benches.

Circuit board – The brain of the phone is made of a mixture of things, such as copper, gold and plastic. Generally printed for ease of manufacture, this is often saved and re-used in other products where possible.

Ceramics – A mobile phone is made up of approximately 20% ceramics, primarily around the antenna area. This is due to being robust, but also being able to let radio signals pass through the phone structure, and can mostly be recovered for re-use.

Copper – Making up around 15% of the phone's construction in various forms, copper is used on everything from circuit boards to wiring. It can be melted down in a smelting furnace and be re-used in things like ski bindings or roofs.

Aluminium – Used in less than 1% of the phone, aluminium is sold to metal refineries. In the refinery, it is smelted and purified and necessary alloying elements are added. The finished metal ingots can be sold again for production of new parts.

Gold – One of the most widely-used precious metals in a phone, it's used in connections within the handset. While making up less than 1% of construction, it is sent to precious metal plants for recovery. 300 grams of gold can be recovered from approximately 1 tonne of recycled mobile phones. The amount of gold extracted saves mining 110 tonnes of gold ore.

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