One of my favorites is the good old gray to black (or darker gray) radial gradient.

我的最爱之一就是从老灰到黑灰的渐变。

youdao

Their fur varies from white to cream to pale yellow or gray, sprinkled with circular, open rosettes of charcoal-gray to black.

皮毛底色从白色到奶油色、黄灰色和灰色不等，中间点缀着木炭灰或者黑色小圆点。

youdao

The Saliyak melange consists of dark-gray to black muddy and silty microclastic rock with intercalation of grayish purple and grayish green calcareous and muddy shale, marl and tuff.

西昆仑赛力亚克混杂堆积由形态、颜色和大小各异的沉积岩块体以及黑色泥质粉砂岩夹灰紫绿色钙质页岩、泥灰岩和层凝灰岩的基质组成。

youdao

The researchers say Anchiornis huxleyi appeared to have a dark gray or black body.

VOA: special.2010.03.16

Should the SEC and law enforcement be expending scarce resources to move from black and white to shades of gray?

FORBES: Insider Trading: Can An Average Investor Find Comfort In The Latest Probe?

Dressed in blue jeans and a gray shirt unbuttoned to reveal a black T-shirt, Mr. Hurwitz, who turns 50 at the end of the month, was about to dissect the long process of reviving "Arrested Development" when a backhoe suddenly roared into view outside an aptly jarring juxtaposition that could have been lifted straight from the series, which frequently parodies California's volatile housing market.

WSJ: Latest 'Development' | Arrested Development | Mitchell Hurwitz | Cultural Conversation by David Mermelstein

Modern sectionals in pale gray wool cozied up to the twin black-marble fireplaces of the parlor.

CNN: Flanders: Europe's best-kept design secret