Officers discovered the Class A drugs on the morning of Saturday, 1 September, when two passengers were stopped after arriving on a flight from Barbados.
The drugs, which had been wrapped in plastic, weighed approximately 8.5kgs and a full forensic analysis will now take place.
Tim Kingsberry, Director of Border Force South said: “It is the job of Border Force to stay one step ahead of the smugglers who would look to bring dangerous drugs like this into the UK.
“Detections such as this are testament to Border Force officers’ expertise. In this case, the drugs seized were estimated to have a potential value of approximately £535,000 once cut and sold on the streets.
“Working with law enforcement colleagues like the National Crime Agency (NCA) we are determined to prevent drug trafficking and bring those responsible to justice.”
Following the seizure by Border Force, the investigation was passed to the NCA.
Two men, Grantley Herbert Thompson, 62, and Jamal Ricardo Walcott, 30, both from Barbados and of no fixed UK address were charged with importing a Class A drug.
The men appeared at Croydon Magistrates Court on 3 September, and were remanded in custody.
They will next appear at Croydon Crown Court on October 1.
The Government’s Serious Violence Strategy, which was launched in April, aims to combat the devastating impact drugs have on levels of serious violence.
It also highlights a strong link between drugs and serious violence and the related harm and exploitation from county lines. The Government has set out the action it will take to tackle this violent and exploitative criminal activity.
The action of Border Force to stop drugs before they get into the country forms a key part of this work.
Border Force officers use hi-tech search equipment to combat immigration crime and detect banned and restricted goods that smugglers attempt to bring into the country.
Nationally, they use an array of search techniques including sniffer dogs, carbon dioxide detectors, heartbeat monitors and scanners - as well as visual searches - to find well-hidden stowaways, illegal drugs, firearms and tobacco which would otherwise end up causing harm to local people, businesses and communities.
Anyone with information about activity they suspect may be linked to smuggling should call the hotline on 0800 59 5000.