But the process is still regarded with suspicion or revulsion by many, perhaps linked to a wider discomfort with the idea of death.
According to the American Society of Embalmers, modern-day embalming took off in the United States during the Civil War, when families would travel to the battlefields to find their dead sons or brothers.
"The Union Army had 'Embalming Surgeons' in the battlefield that would prepare the remains, place them in a coffin and send back to the family by train or horse and buggy," the society's website says.
So what's involved in the embalming process today?
First, the body fluids must be drained and replaced with a formaldehyde-based product, said Richard Arnold, managing director of the Embalmer Training School in Britain and a qualified embalmer for 20 years.
The formaldehyde-based fluid plasticizes the proteins within the body and fights against the bacteria that otherwise would lead to its decomposition, he said.
In cases where the body is expected to remain embalmed for a long period -- rather than for a few weeks or months, as can happen if a funeral is delayed -- the concentration of formaldehyde will be increased. Other chemicals, such as lanolin, can be added to the mix to improve the color and texture of the skin, help break down blood clots or lessen discoloration.
Then comes the process of making the deceased look as realistic and, for the sake of the family, as peaceful as possible, Arnold said. "We do everything from reconstructive surgery to cosmetics and hairdressing."
The cosmetics used in embalming have higher levels of pigment and silicone, he explained, so that when the body is moved in and out of cold storage the cosmetics will expand and contract with the tissue beneath without cracking.
Each embalmer works with individual artistry, he said, with many around the world creating their own mixes of chemicals to achieve the best results in local conditions.
This could be important in Venezuela, where the weather is tropical and power supplies sometimes erratic.
And if a body is going to be displayed for a long time, it's crucial to get it right.
The body of Klement Gottwald, president of then-Czechoslovakia, was embalmed and placed in a mausoleum for display by Communist Party leaders in 1953. But it was taken off display several years later, in part because, it is said, it had begun to decompose.
World leaders aside, Arnold believes embalming is an overlooked and undervalued art that helps regular people if someone dies far from home or must be laid to rest after a delay.
Particularly for families who've lost a relative in sudden or tragic circumstances, it's important to see the loved one looking their best at the last, he adds.
"I've always enjoyed the job," he said. "It's the last thing you can ever do for anybody."
'Magic has gone'
But even with the best of skill, an embalmed body will eventually start to look more waxy or plasticky -- as has been remarked of Lenin's face during his long repose.
It reportedly is under a high-maintenance regime that involves the frequent reapplication of embalming fluids.
Despite this, Lenin is no longer looking as good as he used to, said Tumarkin, who has viewed him several times over the decades in the gloom of his 1920s-style mausoleum, decorated in red, black and white.
It used to make an impression in the Soviet period, when the long lines of visitors leading up to the sarcophagus created a sense of reverence akin to that of a pilgrimage, she said.
But on more recent visits, Tumarkin found much has changed.
"You don't have that any more. You don't have the lines (of people) any more. You just wander in and it's like being in a wax museum -- the magic has long since gone."
It's perhaps a word of warning that Venezuela's leaders should heed as they plan for eternity.