What did Lennie’s Aunt Clara leave him that he has since lost? Why did he like it so much?

Lennie's Aunt Clara gave him a piece of silk. Lennie like to feel it.... to "pet" it.

She was a little bit reassured. “Well, who don’t?” she said. “Ever’body likes that. I like to feel silk an’ velvet. Do you like to feel velvet?”

Lennie chuckled with pleasure. “You bet, by God,” he cried happily. “An’ I had some, too. A lady give me some, an’ that lady was—my own Aunt Clara. She give it right to me—‘bout this big a piece. I wisht I had that velvet right now.” A frown came over his face. “I lost it,” he said. “I ain’t seen it for a long time.”