[求助]学习请大家帮看这石是何材质

清醇人生

<P>以有些年份了.有人说是牛蛋黄.请名家指导<A id=photolink href="http://img776.photo.163.com/lays398/110598049/2616896979.jpg" target=_blank><IMG height=540 alt=2616896979.jpg src="http://img776.photo.163.com/lays398/110598049/2616896979.jpg" width=720></A><A id=photolink href="http://img776.photo.163.com/lays398/110598049/2616897102.jpg" target=_blank><IMG height=540 alt=2616897102.jpg src="http://img776.photo.163.com/lays398/110598049/2616897102.jpg" width=720></A><A id=photolink href="http://img776.photo.163.com/lays398/110598049/2616897233.jpg" target=_blank><IMG height=540 alt=2616897233.jpg src="http://img776.photo.163.com/lays398/110598049/2616897233.jpg" width=720></A><A id=photolink href="http://img776.photo.163.com/lays398/110598049/2616897389.jpg" target=_blank><IMG height=540 alt=2616897389.jpg src="http://img776.photo.163.com/lays398/110598049/2616897389.jpg" width=720></A><A id=photolink href="http://img776.photo.163.com/lays398/110598049/2616897501.jpg" target=_blank><IMG height=540 alt=2616897501.jpg src="http://img776.photo.163.com/lays398/110598049/2616897501.jpg" width=720></A></P>