I've written a lot about provenance in this column over the past months, and it has again been a recurring theme in this week's collectibles markets. In particular, I want to show you the benefits of collecting items which are linked to a specific person.
Choose the right person, and you can have a great investment on your hands. For instance, if you bought a 17th century letter written and signed by King Charles II today, then it is sure to appreciate in value and never be without potential buyers in future years.
Or there are chances to spot opportunities before other investors, like the David Bowie autograph that we sold a few months ago. Most people aren't savvy enough to consider Bowie as their first choice investment - yet autographs by other rock stars of this stature have risen in value by as much as 756% over the last 10 years.
Yet the famous people who have been all over the markets this week aren't monarchs or musicians, but politicians. My advice to people looking to invest in collectibles linked to politicians is: the more remembered the politician is (and will remain), the better.
Like Theodore Roosevelt (1858-1919), the legendary polymath and 26th President of the United States. Roosevelt played a crucial role in bringing together the vast United States of America and establishing its national identity. His legacy remains strong to this day.
As a result, Roosevelt is remembered as one of the greatest American presidents, and consequently commands high values at auction. Take for instance his 'most important and historic' shotgun, which blasted to a final price of $862,500 at an auction in Fairfield, Maine, last month.
Or how about another influential and renowned leader: Sir Winston Churchill. So established is his legacy, that a cigar that was half-smoked by Britain's wartime Prime Minister brought £4,500 ($6,750) earlier this year.
The cigar's value is sure to rise, especially considering that Churchill's autograph has appreciated by 128.8% over the last 10 years. Such rises in value are testament to the strength of political collectibles as alternative assets.
But what about those chances to spot opportunities before other investors that I mentioned? Well, you only need to ask Cherie Blair, wife of the former British Prime Minister Tony Blair. Earlier this month, Cherie was caught trying to sell her husband's signature on eBay for £10.
Why? According to the Blairs' spokesman, Cherie was "cross" that people were selling Tony's signature and tried to undermine the market, undercutting other sellers lower-priced autographs and refunding buyers straight away to make her point.
Despite Cherie's efforts, Tony Blair autographs continue to do a roaring trade on eBay, ranging in price from £149.99 to just £4.99. In future years, Blair is likely to follow his contemporary Bill Clinton in becoming an investment source for collectors of political memorabilia.
For instance, January 2006 saw an engraved invitation to Clinton's inauguration dinner, dated January 20, 1993, sell for an impressive £750 ($1,129) at auction. Here, the question is: what will this same historic document be worth in years to come?
The great thing about political collectibles is that there are opportunities out there whether your budget is hundreds, thousands or tens of thousands. Even in the case of JFK: a newspaper signed by Kennedy on the day he died once sold for £26,000 ($39,000), while letters signed by JFK are available to buy for £3,950 ($5,925).
This, finally brings us onto another item which has cropped up on the market this week: a suite of chairs by the renowned 16th century designed John Linnell which boasts a remarkable provenance to match its $50,000-80,000 pre-sale estimated value.
Over centuries, the chairs have been owned by an English Earl, some of the wealthiest members of America's collecting elite, and have featured at the UK's historic Stansted Park. But among the suite's key selling points is the time is was sat upon by one of the 20th century's most remembered politicians...
Former British Prime Minister Margaret Thatcher's painted portrait at the Carlton Club shows her seated in one of the John Linnell chairs. Like Clinton and Blair, Thatcher's collectibles are gaining momentum as assets - but you don't need to spend $50,000-80,000 to get involved. In fact, you don't need to spend more than £350 ($525) for a quality Thatcher autograph.
With strong legacies, rich histories and ongoing interest in their lives, politicians remain one of the strongest investments on the markets.
You can find more information on investing in memorabilia in our dedicated investments section.
For now, good luck and happy collecting!
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