After cleaning out her garage of electronics belonging to her late husband, the women brought the boxes to the Clean Bay Area recycling center in South Bay, Los Angeles.
The women didn't want a tax receipt, nor did she leave her contact information.
A few weeks later, going through the boxes, staff at the recycling firm made the discovery.
"We really couldn't believe our eyes. We thought it was fake," said Gichun.
The computer is one of only around 200 models of the Apple I computer, made by Steve Jobs, Steve Wozniak and Ron Wayne in 1976. The computer is the first model put together by the trio in their garage.
The firm sold the computer to a private collection for $200,000, and wants to share the proceeds with the mystery donor; company policy is to share half the proceeds with the original owner of a sold item.
"We are looking for her to give her $100,000," explains Gichun, and entreated her to come back to the recycling center to collect her check.
