What region and exact location where the Indian Gift basket was found by archaeologist?

I`m doing an artifact about it, It`s due Tomorrow.
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Archaeologists have identified some Indian baskets artifacts being close to 8000 years old. A team of archaeologists, in eastern Snohomish County, in the State of Washington found a treasure trove of artifacts from the Olcott period, 4,500 to 9,000 years ago, including baskets, spear points, stone knives and scraping tools. I hope this helps. Regards, Warren
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