The Queen will become the first reigning British monarch to reach her 90th birthday next month. (File Photo)
Ahead of Queen's 90th birthday next month, a British artist has etched her portrait, which is believed to be the world's smallest on a tiny speck of gold.
Graham Short, 60, spent three months carving the portrait of Her Majesty, which at five microns is a 20th of the thickness of a human hair.
The portrait is invisible to the naked eye and can only be seen with a medical microscope at 400x magnification.
Mr Short is popular for creating unique works of art which cannot be seen by the naked eye.
It took him around 30 attempts before he was able to complete it.
"I take potassium, magnesium and beta-blockers during the night in an effort to lower my heart rate. Then, while wearing a stethoscope, I engrave using the finest needles possible between my heart beats, Mr Short was quoted by The Daily Express.
"I work from midnight to 5.30am to avoid vibration from passing traffic. If a lorry passes a few blocks away I can feel it through the microscope."
He also has a regular course of Botox injections into his eyelids to "prevent distraction".
The Queen will become the first reigning British monarch to reach her 90th birthday next month.
"Artists all over Britain will be producing portraits of the Queen. I wanted to do something really special, something that none of the seven billion people on the planet could comprehend," he said.
For his canvas he inserted a speck of gold inside the eye of a needle. The thickness of a human hair is measured at 100 microns but his work is just five microns high.
"I am very pleased with the finished result. I've been able to get lots of detail in the crown. This is certainly one of my best pieces," Mr Short added.
His work sells around the world for thousands of pounds.
The Lord's Prayer, engraved on a pin head, took him 40 years. He ditched hundreds of efforts before finishing the 278-letter miniature opus in 2010.