It depends on the place you purchase runescape 3 buy gold. There are many sellers online. game market aren't trustworthy particularly when it comes to the delivery of gold. They may steal your money and then disappear and others may offer fake gold which will vanish within a few hours of playing.
The most effective way to avoid being banned from RuneScape is to purchase OSRS gold from reliable sellers. RSorder assures authentic currency delivery within the timeframe they specify through their live chat or customer service agents. The sellers who are reputable will guarantee your OSRS gold or buy runescape accounts you purchase from them is genuine that is, you may use the gold within the game to purchase additional items.